阅读说明：本技术 用于处理非织造网的液体聚合物溶液 (Liquid polymer solution for treating nonwoven webs ) 是由 M·D·布切夫斯基 Z·美里 S·沙哈尔 于 2019-04-02 设计创作，主要内容包括：本发明涉及生产吸水性纺织复合材料的方法,该方法包括使用聚合物复合溶液和纺织材料(非织造、织造和其他)。纺织材料浸渍有复合聚合物溶液,在热处理后该复合溶液原位交联。更具体地,本发明涉及吸收性纺织复合制品,该吸收性纺织复合制品包含纺织纤维和渗透该纺织纤维的聚合物网络,该聚合物网络包含在不存在非聚合物交联剂的情况下交联至合成聚合物的天然聚合物。该纺织复合制品表现出对水性介质(例如食物液体、化妆品液体、药物液体或人体分泌物)的优异吸收性。(The invention relates to a method for producing water-absorbing textile composite materials, comprising the use of polymer composite solutions and textile materials (nonwoven, woven and others). The textile material is impregnated with a composite polymer solution which is crosslinked in situ after heat treatment. More specifically, the present invention relates to absorbent textile composite articles comprising textile fibers and a polymer network penetrating the textile fibers, the polymer network comprising a natural polymer crosslinked to a synthetic polymer in the absence of a non-polymeric crosslinking agent. The textile composite article exhibits excellent absorption of aqueous media, such as food liquids, cosmetic liquids, pharmaceutical liquids or human secretions.)

1. A textile composite article, wherein the textile composite article comprises textile fibers and a polymer network penetrating the textile fibers, the polymer network comprising a natural polymer crosslinked to a synthetic polymer in the absence of a non-polymeric crosslinking agent, the textile composite article having a water absorption at least 10% greater than an identical textile without the polymer network.

2. The textile composite article of claim 1, wherein the textile composite article is biodegradable.

3. A polymer composite aqueous solution for improving the water absorption of textile materials treated with the polymer composite aqueous solution, wherein the polymer solution comprises a network of natural and synthetic polymers that self-crosslink under controlled conditions of temperature and time and in the absence of a non-polymeric crosslinking agent.

4. The aqueous polymer composite solution of claim 3, wherein the textile material is of the non-woven, woven or knitted type, the textile material having a density of 30g/m prior to treatment with the aqueous polymer composite solution²To 90g/m²。

5. A method of preparing the aqueous polymer composite solution of claim 3, wherein the method comprises:

a) preparing an alkaline alkali solution;

b) preparing an aqueous solution of the Synthetic Polymer (SP) in acidic form, and then treating the aqueous solution of the Synthetic Polymer (SP) in acidic form with the alkaline solution of (a) to obtain an aqueous solution of the Synthetic Polymer (SP) in salt form at a concentration of 1 to 10 wt%, preferably 2 to 5 wt%;

c) preparing an aqueous solution of natural polymer NP at a concentration of 1 to 10 wt% (preferably 2 to 5 wt%) under heating;

d) mixing the SP solution in salt form obtained in (b) with the NP solution obtained in (c) under heating and stirring to obtain a stable polymer composite aqueous solution suitable for use as an impregnation substance to impart high water absorption to textile materials;

and optionally also,

e) adding to the composite aqueous solution obtained in (d) at least one adjunct material selected from the group consisting of plasticizers, surfactants, deodorants, perfumes and preservatives.

6. The process according to claim 5, wherein the Synthetic Polymer (SP) is chosen from linear or branched graft homopolymers or copolymers made from vinyl acid monomers, such as acrylic acid, maleic anhydride, itaconic anhydride, etc., optionally in combination with other types of vinyl monomers not necessarily containing carboxylic acid functions.

7. The method according to claim 5, wherein the SP is a copolymer based on maleic anhydride and/or maleic acid, preferably a copolymer of Styrene Maleic Anhydride (SMA), a copolymer of isobutylene and maleic anhydride (e.g. under the trade name Isobam)^TMCommercially available copolymers sold) or copolymers of methyl vinyl ether and maleic acid (e.g., under the trade name Gantrez)^TMCommercial copolymers sold).

8. The method according to claim 5, wherein the Natural Polymer (NP) is a biopolymer selected from the group consisting of proteins, soy protein, collagen biopolymers, gelatin, collagen hydrolysates, albumin, guar gum or starch and casein.

9. The method according to claim 5, wherein the Natural Polymer (NP) is a biopolymer selected from the group consisting of polypeptides, proteins, polysaccharides, polyesters and lignins (in natural form or modified by chemical or enzymatic hydrolysis).

10. The method of claim 5, wherein the Natural Polymer (NP) is a biopolymer selected from the group consisting of: water-soluble phospholipids (e.g., lecithin), polypeptides, or proteins (e.g., gelatin, albumin, etc.); or polysaccharides such as cellulose, alginate, dextran, chitosan, and the like.

11. The method according to claim 5, wherein the Natural Polymer (NP) has amino and/or hydroxyl groups capable of crosslinking to COOH groups in SP under high temperature conditions and for a selected period of time.

12. Use of the textile composite article of claim 1 for an absorbent product.

13. Use according to claim 12, wherein the absorbent product is selected from: cleaning wipes, household or industrial cleaning or maintenance articles, hand wipes, personal wipes, cosmetic or sanitary wipes, baby wipes, facial wipes, sanitary absorbent pads, underpants, wound dressings and the like.

Technical Field

The present invention relates to a method for producing water-absorbent textile materials, such as nonwoven (woven), woven (woven) or other textile material types, and to associated absorbent products.

Background

In the art, there are known methods of manufacturing absorbent textile materials, which can be divided into two different types: a) a method using textile fibers (textile fibers) and a polymer absorbent; and b) a process using a preformed textile material and a reactive liquid medium.

Only the method of using a prefabricated textile material and a reactive liquid medium is discussed below.

b) Method of using a preformed textile material and a reactive liquid medium

These processes are characterized by the impregnation of a traditional prefabricated textile material (for example of the non-woven, knitted or braided type) with a fluid substance in the form of a solution, emulsion or suspension, and by the in situ (in situ) generation of the polymeric absorbent during the drying of the impregnated wet textile material or after drying and suitable thermal treatment. Representative methods known in the art: b1) a method using a polymerizable impregnating substance (impregnation mass); and b2) a method of using a cross-linkable impregnating substance.

b1) Method for using polymerizable impregnating substances

In these processes, the impregnating liquid polymerizes the partially neutralized acidic vinyl monomer in situ directly on the synthetic nonwoven substrate.

These methods can be found in U.S. patents 4,537,590, 4,540,454, 4,573,988; 4,676,784, 5,567,478, 5,962,068, 6,417,425 and 6,645,407.

b2) Method of using crosslinkable impregnating substances

In these processes, a textile material, prefabricated as a non-woven, woven or other known type, is impregnated with a fluid substance in the form of a solution or emulsion, containing a polymer in dissolved or dispersed state or mixed with an auxiliary material which is a cross-linking agent active at temperature and induces the in situ generation of a polymeric absorbent. Such methods may have more variations:

i) method for using impregnation materials containing self-crosslinking synthetic polymers

Various methods of crosslinking a substantially linear acrylic polymer through its pendant groups are described. Upon appropriate heating, the side groups will react with each other. Any combination of monomers to carry out such reactions as described in U.S. patents 4,057,521, 4,861,539, 4,962,172, 4,963,638, 5,280,079 and 5,413,747 may be used.

Impregnation substances based on self-crosslinking polymers have the disadvantage of incomplete crosslinking, for which reason more than 10% of the final product is lost in the process in connection with extraction of the monomers, initiators and organic solvent residues used during the polymerization. Furthermore, the value of free absorbency (free absorbency) of the resulting crosslinked polymer is low (less than 50g/g in 0.9% NaCl solution), and the product is not safe.

ii) method of using an impregnating substance containing a synthetic polymer and a crosslinking agent

It is further known from U.S. Pat. Nos. 2,988,539, 3,393,168 and 3,514,419 that water swellable (water swellable) crosslinked carboxylic acid copolymers can be prepared. However, these prior art copolymers are all crosslinked during copolymerization or after polymerization, with the carboxylic acid groups subsequently neutralized to form water-swellable polyelectrolytes, and therefore, these prior art polyelectrolytes cannot be crosslinked in situ as a coating on a substrate or a flexible film thereof.

U.S. Pat. nos. 3,926,891, 3,980,663 and 4,155,957 propose a main combinatorial class of chemical structures that can be used as crosslinkers for polymers with free carboxyl chemical functionality. It has also been shown that the crosslinking reaction occurs on saturated carbons based on a mechanism known as nucleophilic substitution. The carboxylate ions on the polymer act as nucleophiles, while the crosslinker is the substrate for nucleophilic attack (nucleophilicity attack).

Cheng et al in us patent 5,693,707 propose an aqueous polymer composition comprising 10 to 40 wt% of a polymer in water consisting essentially of 20 to 90 wt% of an alpha, beta-ethylenically (ethylenically) unsaturated carboxylic acid monomer and 10 to 80 wt% of one or more softening monomers, the aqueous composition adjusted to a pH of 4-6 with an alkali metal hydroxide or alkaline earth metal hydroxide, and further comprising 0.1 to 3 wt% of a zirconium crosslinking salt. Such aqueous compositions are applied to nonwoven and woven substrates to make absorbent textile webs.

Goldstein et al, in U.S. patent 6,506,696, show that the method of forming the high performance nonwoven web of the present invention comprises: applying an aqueous polymer emulsion comprising a polymer having a dual cross-linkable functionality to a synthetic-based nonwoven web, wherein the dual cross-linkable polymer comprises an acetoacetate functionality and a carboxylic acid functionality; removing the water to crosslink the crosslinkable polymer with an effective amount of polyaldehyde and an effective amount of polyethylenimine compound.

Soerens Dave Allen in U.S. patent 7,205,259 proposes an absorbent adhesive desiccant composition that spontaneously crosslinks at a temperature below about 120 ℃ after application to a substrate. Absorbent binder desiccant compositions comprise a monoethylenically unsaturated polymer (e.g., a carboxylic, sulfonic or phosphoric acid or salt or quaternary ammonium salt thereof), and an acrylate or methacrylate ester containing an alkoxysilane functionality, or a monomer capable of copolymerization with a compound containing a trialkoxysilane functionality and then reacting with water to form silanol groups, and a desiccant component. The absorbent adhesive desiccant composition is particularly useful in the manufacture of a variety of humidity control articles.

In addition to the many variations in controlling the crosslinking reaction, various chemical compositions (polymers and crosslinkers) have been discovered in the art in U.S. Pat. nos. 3,983,271, 4,066,584, 4,320,040, 4,418,163, 4,731,067, 4,855,179, 4,880,868, 4,888,238, 5,698,074, 5,997,791, 6,150,495, 6,162,541, 6,241,713, 6,773,746, and 6,824,650.

iii) method of using an impregnating substance containing a biopolymer and a cross-linking agent

Weerawara et al in U.S. patent 7,300,965 provide a mixed polymer network having superabsorbent properties. The composition is obtainable by reacting a carboxyalkyl cellulose and a synthetic water soluble polymer having a carboxylic acid or carboxylic acid derivative substituent with a crosslinking agent. The cross-linking agent reacts with at least one of the carboxyalkyl cellulose or the water soluble polymer to provide a network. Suitable crosslinking agents include those reactive with carboxylic acid groups.

Representative organic crosslinking agents reactive with carboxylic acid groups include: diols and polyols, diamines and polyamines, diepoxides and polyepoxides, polyoxazoline functionalized polymers, and amine alcohols (aminols) having more than one amino group and more than one hydroxyl group.

Representative inorganic crosslinking agents reactive with carboxylic acid groups include multivalent cations and polycationic polymers. Exemplary inorganic crosslinking agents include aluminum chloride, aluminum sulfate, and ammonium zirconium carbonate with or without carboxylic acid ligands, such as succinic acid (dicarboxylic acid), citric acid (tricarboxylic acid), and butanetetracarboxylic acid (tetracarboxylic acid). Water soluble salts of ferric and ferrous zinc with copper may be used as cross-linking agents. Representative carboxylic acid cross-linking agents include dicarboxylic acids and polycarboxylic acids. U.S. Pat. Nos. 5,137,537, 5,183,707, and 5,190,563 describe the use of C2-C9 polycarboxylic acids containing at least three carboxyl groups (e.g., citric acid and oxydisuccinic acid) as crosslinkers. Suitable polycarboxylic acid crosslinking agents include: citric acid, tartaric acid, malic acid, succinic acid, glutaric acid, citraconic acid, itaconic acid, tartaric acid monosuccinic acid, maleic acid, 1,2, 3-propanetricarboxylic acid, 1,2,3, 4-butanetetracarboxylic acid, all-cis-cyclopentanetetracarboxylic acid, tetrahydrofurantetracarboxylic acid, 1,2,4, 5-benzenetetracarboxylic acid and benzenehexacarboxylic acid. Crosslinking may be achieved by heating at a temperature and for a time sufficient to effect crosslinking. The carboxymethyl cellulose solution containing the crosslinking agent or synthetic water soluble polymer and the crosslinking agent may be air dried or solvent precipitated and then crosslinked. The crosslinking time and temperature will depend on the crosslinker and polymer used.

Sun et al, in U.S. patent 6,689,378, propose a method of immobilizing uncomplexed cyclodextrins and complexed cyclodextrins on a polysaccharide-containing substrate (e.g., cellulosic fibers) by covalent bonding. The cellulose/cyclodextrin composition can be used in all types of cellulose fiber containing articles, such as paper towels and personal care articles.

Useful polymeric anionic reactive compounds are compounds having a repeating unit comprising two or more anionic functional groups that will covalently bond to hydroxyl groups of the substrate. Exemplary polymeric anionic reactive compounds include ethylene/maleic anhydride copolymers described in U.S. patent 4,210,489. Other examples are vinyl/maleic anhydride copolymers and copolymers of epichlorohydrin with maleic anhydride or phthalic anhydride. Copolymers of maleic anhydride with olefins are also contemplated, including poly (styrene/maleic anhydride). U.S. patent 4,242,408 discloses copolymers and terpolymers of maleic anhydride that may be used.

Similar to the in situ polymerizable systems, crosslinkable impregnating substances have the disadvantage: under the conditions of said heat treatment, the crosslinking is incomplete, there being a permanent possibility that the crosslinking agent is extracted in addition to the soluble polymer during use of the textile product, which is more dangerous for human health than monomer or polymerization aid residues. The presence of biopolymers in the mixtures used for the treatment of textile materials does not contribute to improving the chemical conversion yield during crosslinking. With regard to the use of macromolecular crosslinking agents, no mention is made of the purity of these products (as such being the result of the synthesis process) or the extractability in aqueous solutions used as swelling media.

Particular disadvantages of the processes known in the art for obtaining absorbent textiles are: those products are not environmentally friendly. Most of the above polymeric absorbents are synthetic products that, due to their chemical structure, do not have the ability to biodegrade in a particular active biological medium (i.e., live compost). Furthermore, although the absorbent textile containing the biopolymer is biodegradable, its value of free absorbency is small. Another drawback of the known absorbent textile is that: the polymer networks contained in such textiles are obtained by using cross-linking agents that may pose a health hazard to the end user.

Disclosure of Invention

The present invention eliminates the disadvantages of the processes known in the art for obtaining absorbent textiles by providing a new method of treating textiles and forming a new textile composite article with improved water absorption and biodegradability. The novel process utilizes a polymer composition impregnated with an aqueous textile, the polymer composition being in the form of a solution and comprising at least two types of soluble polymers (synthetic and natural), the composition being free of a separate non-polymeric crosslinking agent. The two types of polymers are combined in a predetermined ratio selected such that: when the textile is impregnated with the polymer composition and exposed to a heat treatment, the polymer penetrates into the textile fibers and self-crosslinks within the textile. Depending on the type of liquid medium contacted, the resulting composite textile in dry form has a free absorbency at least 10% higher than that of the unimpregnated textile material. The resulting textile is also characterized by high biodegradability. More specifically, the resulting composite textile in dry form has a free absorbency that is at least 10% higher, preferably at least 20% higher, more preferably 30%, 40%, 50%, 60%, 70%, 80%, 90% or more higher than the unimpregnated textile material.

In the present description, the terms fabric, textile, web, are used interchangeably, whether or not in combination with the word "material".

It is another object of the present invention to provide a textile composite article comprising fibers and a polymer network penetrating the textile fibers, the polymer network comprising a natural polymer crosslinked to a synthetic polymer in the absence of a non-polymeric crosslinking agent. The water absorption of the textile composite article is at least 50% higher compared to the same textile without the polymer network of the infiltrated textile fibers.

It is another object of the present invention to provide novel polymer compositions wherein the natural polymers activate the biodegradation of the synthetic polymers and impart excellent biodegradability to the system.

It is another object of the present invention to provide novel polymer compositions made from at least two types of soluble polymers (synthetic and natural), wherein the natural polymer activates the cross-linking of the synthetic polymer under heat and allows for excellent free absorbency of textiles impregnated with such compositions and dried when exposed to aqueous liquids.

Natural polymers are biopolymers which are used as crosslinkers for synthetic polymers and activators of biodegradation processes.

It is another object of the present invention to provide a textile composite article having an internal pattern of permeable polymeric material that at least partially permeates into the textile resulting in a pattern of impregnated areas in the textile. After heat treatment and drying of the impregnated textile, a textile composite article is obtained which has improved water absorption upon exposure to aqueous liquids.

It is another object of the present invention to provide novel polymer network compositions which are compatible with different additives used in the textile industry (e.g. plasticizers, active surfactants, dyes, fragrances, odor control agents, bacteriostats, etc.) in stable aqueous solutions without affecting the water absorption properties or the biodegradability of the textile material.

Another object of the present invention is to provide a novel polymer network composition in the form of a solution suitable for use as an impregnation substance for any non-woven, woven or knitted textile material made of synthetic fibers (polypropylene, polyester, polyvinyl alcohol, etc.), natural fibers (cellulose, viscose, cotton, wool, PLA, etc.) or a mixture of synthetic and natural fibers, preferably with a density of 30g/m²To 90g/m². The textile material may be biodegradable as such (e.g., when made of PLA), or become biodegradable after being impregnated with a polymer network and dried to form the composite absorbent textile of the present invention.

It is another object of the present invention to provide novel polymeric aqueous compositions which self-crosslink upon thermally driven removal of water from textile materials impregnated with such compositions, resulting in composite absorbent textile materials having free spaces which allow for rapid ingress and absorption of liquid media in the textile materials when the textile is exposed to aqueous liquids.

Preferably, the combined ratio of the two polymers in water is chosen so as to obtain an aqueous solution which is thermodynamically stable and suitable for impregnation into the fabric and self-crosslinking under controlled thermal conditions (temperature and time).

The textile material treated with the polymer composition of the present invention is characterized by improved water absorption and biodegradability. With respect to biodegradability, when a textile comes into contact with an aqueous biological medium and begins to absorb this medium, the composite polymeric material impregnated in the textile swells and is converted into a gel-like material within or on the surface of the textile (the textile acts as a support).

According to other embodiments of the present invention, there is provided a polymer composite solution for forming an absorbent textile material in dry form and in the form of a gel obtained after swelling in different aqueous media, which is still safe upon contact with humans, which is environmentally friendly, giving the textile material used significant ecological properties.

According to another aspect, the present invention provides a method of preparing a polymer composite aqueous solution for improving the water absorption of a substrate (e.g., fabric) treated with the polymer composite, the method comprising the steps of:

a) preparing an alkaline alkali solution;

b) preparing an aqueous solution of the Synthetic Polymer (SP) in an acidic form, and then treating the aqueous solution of the Synthetic Polymer (SP) in an acidic form with the alkaline solution of (a) to obtain an aqueous solution of the Synthetic Polymer (SP) in a salt form at a concentration of 1 to 10 wt%, preferably 2 to 5 wt%;

c) preparing an aqueous solution of natural polymer NP at a concentration of 1 to 10 wt% (preferably 2 to 5 wt%) under heating;

d) mixing the SP solution in salt form obtained in (b) with the NP solution obtained in (c) under heating and stirring to obtain a stable polymer composite aqueous solution suitable for use as an impregnation substance to impart high water absorption to textile materials;

and optionally also,

e) adding to the composite aqueous solution obtained in (d) at least one adjunct material selected from the group consisting of plasticizers, surfactants, deodorants, perfumes and preservatives.

According to a preferred embodiment, the Synthetic Polymers (SP) used according to the invention are made from monomers bearing carboxylic acid groups or carboxylic anhydride groups. More specifically, the SPs suitable for use in the present invention are linear or branched, grafted homopolymers or copolymers made from vinyl acid monomers (e.g., acrylic acid, maleic anhydride, itaconic anhydride, etc.) optionally in combination with other types of vinyl monomers that do not necessarily contain carboxylic acid functionality.

Preferably, the natural polymer is a biopolymer selected from the group consisting of proteins, soy protein, collagen biopolymers, gelatin, collagen hydrolysates, albumin, guar gum or starch and casein.

Preferably, the synthetic polymer is a copolymer based on maleic anhydride (maleic acid), for example a copolymer of Styrene Maleic Anhydride (SMA), a copolymer of an olefin with maleic anhydride, for example a copolymer of isobutylene and maleic anhydride (for example under the trade name Isobam @)^TMCommercially available copolymers sold) or copolymers of methyl vinyl ether and maleic acid (e.g., under the trade name Gantrez)^TMCommercially available copolymers sold), poly (decylvinyl ether-alt-maleic anhydride), poly (ethylvinylether-alt-maleic anhydride), poly (maleic acid-co-propylene), poly (n-butylvinylether-alt-maleic anhydride), poly (octadecene-alt-maleic acid)Anhydride), poly (propylene-alt-maleic acid) or poly (maleic acid-co-dodecyl methacrylate).

According to a preferred embodiment, the total content of free carboxylic acid groups in the SP of the invention is from 0.009mol/g SP to 0.015mol/g SP. More specifically, the free carboxylic acid groups of the synthetic polymer SP are in the salt state, corresponding to a degree of neutralization of 49-99% (preferably 60% to 95%, most preferably 65% to 90%).

According to a preferred embodiment, the average molecular weight of the SPs used in the present invention is from 50kDa to 1,000kDa, preferably from 100kDa to 750kDa, more preferably from 150kDa to 500 kDa.

According to a preferred embodiment, the natural polymer NP used in the present invention is a biopolymer selected from the group consisting of polypeptides, proteins, polysaccharides, polyesters and lignins (in natural form or modified by chemical or enzymatic hydrolysis). More preferably, the NPs used in the present invention are water-soluble phospholipids (e.g., lecithin), polypeptides or proteins (e.g., gelatin, albumin, etc.); or polysaccharides such as cellulose, alginate, dextran, chitosan, and the like; it has at least one of the following characteristics:

a) an average molecular weight of 5 to 100kDa, preferably 25 to 50kDa, more preferably 75 to 100 kDa;

b) the relative concentration of free chemical groups (e.g., amino or hydroxyl groups) is from 0.005mol/g NP to 0.01mol/g NP, more preferably from 0.001mol/g NP to 0.002mol/g NP; and

c) hydrophilic, capable of forming a hydrogel in an aqueous environment and capable of being integrated in textile fibers.

According to a preferred embodiment, the biopolymer used according to the invention has NH₂Groups or OH groups (which cross-link to COOH groups of the synthetic polymer under high temperature conditions and for a selected period of time), and thus have the ability to cross-link to form ester and amide linkages between polymer backbones. In addition, the biopolymer of the present invention can activate biodegradation of a textile impregnated with the SP-NP complex solution of the present invention.

According to other preferred embodiments, the polymer composite solution used in the present invention is a stable solution, and may further comprise at least one additive selected from plasticizers, antibacterial agents, surfactants, deodorants, perfumes, preservatives, and the like. The polymer composite solution is suitable for impregnation into fabrics and also for self-crosslinking under controlled temperature and time conditions.

Preferably, the textile has a density of 30g/m²To 90g/m²To allow sufficient penetration of the polymer composite solution into the textile material.

Drawings

The invention will now be described with reference to the accompanying drawings, in which:

fig. 1 is a graph showing the correlation between the viscosity of an SP-NP complex solution, the neutralization degree of a Synthetic Polymer (SP), and solution stability. SP is represented by SMAC (styrene maleic acid copolymer) in the form of a salt neutralized with sodium hydroxide. The Natural Polymer (NP) is represented by gelatin. The following polymer solutions were tested: 100% SMAC; 90% SMAC and 10% gelatin; 70% SMAC and 30% gelatin. As further described in example 1, the SMACs used had different degrees of neutralization. It is noted from fig. 1 that the presence of the natural polymer gelatin causes a decrease in the viscosity of the polymer composite solution if the degree of neutralization of the synthetic polymer is 30% to 60%. If the degree of neutralization is greater than 60%, the presence of the natural polymer causes an increase in the viscosity value of the composite solution compared to the same solution without the natural polymer. With respect to the stability of the polymer composite solution, it should be noted that if the neutralization degree of the synthetic polymer SMAC is more than 30%, the composite solution containing SMAC and gelatin is stable.

FIG. 2 is a graph showing the relative absorption RQ of a nonwoven sample (impregnated with a polymer composite solution comprising a synthetic polymer and gelatin) by heat treatment₁A graph of the effect of (c).

Figure 3 is a graph showing the effect of fiber type on the water absorbency of a textile impregnated with a polymer composite vs un-impregnated textile.

Fig. 4 is a schematic illustration of the process that takes place between the textile material and the polymer network under heated conditions to provide a textile composite article of the invention.

Detailed Description

The polymer composite solution within the object of the present invention is a new textile treatment, hereinafter referred to as Impregnation Composition (IC), for treating any type of textile, preferably non-woven textile, to produce a highly absorbent textile material.

The polymer composite solution comprises a Synthetic Polymer (SP) in the form of a salt, a Natural Polymer (NP), an additive (a) and water (W).

The ratio of textile material TEX (before treatment) to impregnating composition IC [ IC ═ SP + NP + a ] was 85: 25 to 99: 1 (in dry weight%).

The ratio SP/NP of Synthetic Polymer (SP) in salt form to Natural Polymer (NP) was 70: 30 to 95: 5 (in dry weight%).

The ratio A/(SP + NP) of additive (A) to polymer is 0.5 to 5 (in dry weight%).

The water content in the polymer composite solution is 79 wt% to 99 wt%.

The synthetic polymer salt SP may be a commercially available polymer having the following characteristics:

a) linear or branched graft homopolymers or copolymers comprising a vinyl acid monomer (e.g., acrylic acid, maleic anhydride, itaconic anhydride, etc.) with or without a combination with other types of vinyl monomers that do not contain a carboxyl group;

b) the total content of free carboxyl groups is 0.009 mol/g: 0.0095mol/g to 0.01 mol/g: 0.0.15 mol/g;

c) the free carboxyl groups of the synthetic polymer SP are in the salt state, corresponding to a degree of neutralization of from 49% to 99%, preferably from 60% to 95%, most preferably from 65% to 90%;

d) by using a strong inorganic base substance (for example, a hydroxide, bicarbonate or carbonate of lithium, sodium, potassium or ammonium, preferably a hydroxide of lithium, sodium, potassium or ammonium), a salt state of the synthetic polymer is obtained;

e) the average molecular weight of the synthetic polymer SP is from 50,000Da to 1,000,000Da, preferably from 100,000Da to 750,000Da, most preferably from 150,000Da to 500,000 Da.

Preferably, the natural polymer NP is a commercially available biopolymer belonging to the following classes: proteins, carbohydrates, biopolyesters or lignin (either in native form or modified by chemical or enzymatic hydrolysis); proteins and carbohydrates which are wholly water soluble are preferred and have the following properties:

d) an average molecular weight of 5,000Da to 100,000Da, preferably 25,000Da to 50,000Da, more preferably 75,000Da to 100,000 Da;

e) the free chemical functional group being NH₂、OH-CH₂、OH-C₆H_3-5(ii) a The content of the free chemical functional group is 0.001mol/g to 0.002mol/g, preferably 0.005mol/g to 0.01mol/g, as a single type or more.

Suitable additives a are: plasticizers, antimicrobials, active surfactants, deodorants, perfumes, preservatives, etc., in amounts related to properties other than absorbency.

The polymer composite solution is a stable solution of the polymer materials SP and NP, and does not phase separate under the condition of storage or careful treatment.

Without being bound by theory, the polymer composite solution may penetrate into the textile fibers and self-crosslink under heat treatment conditions at a temperature of 100 ℃ to 250 ℃ and preferably for a period of 2 minutes to 30 minutes.

The resulting textile is a composite textile article having an interior pattern of permeable polymeric material at least partially permeated into the textile. After heat treating the impregnated textile at a temperature of from 100 ℃ to 250 ℃ and drying the impregnated textile, a textile composite article is obtained which has an improved water absorption rate when exposed to an aqueous liquid.

Fig. 4 shows a schematic of the process that takes place between the textile material and the polymer network under heated conditions to provide a textile composite article of the invention.

A method for preparing an aqueous polymer composite solution for improving the water absorption of a substrate (e.g., fabric) treated with a polymer composite, the method comprising the steps of:

a) preparing an alkaline alkali solution;

b) preparing an aqueous solution of the Synthetic Polymer (SP) in an acidic form, and then treating the aqueous solution of the Synthetic Polymer (SP) in an acidic form with the alkaline solution of (a) to obtain an aqueous solution of the Synthetic Polymer (SP) in a salt form at a concentration of 1 to 10 wt%, preferably 2 to 5 wt%;

c) preparing an aqueous solution of natural polymer NP at a concentration of 1 to 10 wt% (preferably 2 to 5 wt%) under heating;

d) mixing the SP solution in salt form obtained in (b) with the NP solution obtained in (c) under heating and stirring to obtain a stable polymer composite aqueous solution suitable for use as an impregnation substance to impart high water absorption to textile materials;

and optionally also,

e) adding to the composite aqueous solution obtained in (d) at least one adjunct material selected from the group consisting of plasticizers, surfactants, deodorants, perfumes and preservatives.

Textile materials for use with the polymer composite solution include pre-formed textile materials (e.g., nonwoven, woven, or any other type known in the art and commercially available) formed from synthetic or natural fibers or a mixture of synthetic and natural fibers. The preferred textile material consists of a density of 30g/m²To 90g/m²(preferably 40 g/m)²To 80g/m²More preferably 50g/m²To 70g/m²) The synthetic fiber of (2).

Impregnation of the textile material may be carried out using any equipment known in the art, such as spray equipment, padding machines, roll coaters, reverse roll coaters, knife devices, and the like.

The further processing of the wet-spun material depends on the initial density of the material and the degree of impregnation selected. For example:

a) if the density of the textile material is initially higher than 70g/m²The wet textile material is first dried in a stream of hot air at a temperature of 50 ℃ to 90 ℃ (preferably 55 ℃ to 85 ℃, most preferably 60 ℃ to 80 ℃),so obtained solid composite materialThe moisture content of the (textile + composite polymer) is less than 12 wt.% (preferably less than 10 wt.%, most preferably less than 8 wt.%)%) followed by a supplementary heat treatment in hot air steam at a temperature of 90 ℃ to 180 ℃ (preferably 100 ℃ to 170 ℃, most preferably 110 ℃ to 160 ℃) for 5 minutes to 180 minutes (preferably 10 minutes to 150 minutes, most preferably 15 minutes to 120 minutes);

b) if the density of the textile material is initially below 70g/m²The wet woven material is then subjected to a single heat treatment at a temperature of from 100 ℃ to 150 ℃ for from 180 seconds to 300 seconds (preferably at a temperature of from 140 ℃ to 180 ℃ for from 60 seconds to 180 seconds, most preferably at a temperature of from 200 ℃ to 250 ℃ for from 30 seconds to 120 seconds).

After the heat treatment, the textile material is cooled at room temperature and finally packaged.

The resulting textile material has improved water absorption and can be used in a variety of applications such as cleaning wipes, household or industrial cleaning or maintenance articles, hand wipes, hand towels (which let the user feel that the towel remains dry but can also absorb moisture), personal hygiene articles, cosmetic or sanitary wipes, baby wipes, facial towels, panty cores or wound dressing cores, sanitary absorbent pads and any other similar applications.

Test method

1. Characterization of polymer solutions comprising synthetic polymer, natural polymer and auxiliaries:

the viscosity of the solution was evaluated at a temperature of 25 ℃ using a viscometer, ViscoStar Plus (Fungilab, spain), using the volume of the solution in relation to the type of rotor L1.

The stability of the polymer solution for impregnation was assessed as stable or unstable if the analyte solution showed a precipitate after centrifugation of 25ml of solution at 5000rpm for 30 minutes. The test was performed using a laboratory centrifuge GLC-2B Sorvall (Thermo Scientific) at ambient temperature.

2. Free absorbency

The following measurements were performed:

-M_tex[ gram of]-the mass of the dry textile material for impregnation weighed with a semi-analytical balance;

-M_twstart[ gram of]-weighing the mass of the wet raw material obtained from the sample;

-M_tid[ gram of]-the mass of the drained textile material after impregnation;

-M_IC[ gram of]-the mass of dry polymer composite found in the textile after impregnation, calculated as follows:

M_IC＝M_texIMD/100 g

The degree of impregnation of the textile material can be determined using the following formula:

[IMD]_{dry matter}＝M_IC/(M_tex+M_IC)*100，％

Absorbency evaluation of textile materials:

2.1 absorption of the unimpregnated textile Material Q₁The method comprises the following steps: the textile sample M-tex was added to 150ml of liquid (to which the absorbency of the textile sample was required) so that the entire surface of the textile material was covered with liquid, and kept in contact without shaking for 60 minutes. The material was then removed from the liquid and hung vertically for 15 minutes to drain excess liquid. The drained sample of textile material was weighed and the resulting value was recorded as M-tex-wet.

Absorption Q of unimpregnated textile materials₁Can be obtained by the following formula:

Q₁not (M-tex-wet-M-tex)/M-tex, (g/g)

₂2.2 absorption of impregnated textile Material Q

Weighing the textile sample by an industrial balance to obtain a value M_tex. The textile sample is then impregnated with a selected mass of liquid (distilled water, impregnation solution or other type of solution) by using a laboratory spray device. The wet material thus obtained is weighed again and has a value M_twstart. If the value is higher than a predetermined degree of Impregnation (IMD), the wet sample is pressed with a glass rod to remove excess impregnation liquid, thereby finally obtaining a wet sample (mass M)_tid). Next, the wet sample was placed in a closed glass beaker for 30 minutes to avoid evaporation of the liquid.

The absorbency of a sample of textile material can be obtained by the following formula:

Q_2-TEXIC＝[M_tid–(M_tex+M_IC)]/(M_tex+M_IC)，(g/g)

2.3 relative absorption Rate

RQ denotes the absorption Q of the impregnated textile material₂Absorption Q of the same unimpregnated textile material₁The ratio of (a) to (b).

The relative absorption rate can be calculated using the following formula:

[RQ]₁＝Q₂/Q₁or is or

[RQ]₂＝[(RQ₁)–1]*100，(％)

Examples

Example 1

Stock solutions of synthetic polymer, natural polymer and inorganic base were prepared as follows:

a) stock solutions of synthetic polymer solutions

42.6g of SMAc styrene/maleic acid copolymer [ prepared as in U.S. Pat. No. 7,985,819 ] (water content 8%, average molecular weight 450,000Da, containing 0.0091mol/g free carboxyl groups) in powder form and 358g of demineralized water were added to a mixing vessel with stirring means, the contents were mixed at 80 ℃ for 1 hour to completely dissolve the synthetic polymer, and finally the polymer solution was cooled to 40 ℃. Finally, 400g of a 10% dry weight solution of the SMAc polymer was obtained.

b) Stock solution of sodium hydroxide solution

400g of a 10% NaOH solution (from sodium hydroxide particles of purity 98.9%) by dry weight were prepared with demineralized water using a mixing vessel equipped with a stirring device equipped with a heating-cooling jacket.

c) Stock solutions of natural polymer solutions

400g of a gelatin type A solution (as natural polymer-NP) having 200Bloom and 14% water content, with a dry weight of 10%, were prepared by dissolving 46.5g of the natural polymer in 354g of demineralized water using a mixing vessel, stirring at a temperature of 40 ℃ for 1 hour (rotor speed not exceeding 60rpm) to ensure perfect homogenization of the solution.

Further, three sets of complex solutions were prepared using the three types of solutions prepared above by diluting the stock solutions with demineralized water as follows:

Set-SOL1 was gelatin-free and consisted of 12 3% strength solutions, with synthetic polymers having different degrees of neutralization ranging from 0% to 110%.

Set-SOL-2 contained 10% gelatin to SMAc in 12 solutions with a concentration of 3%, wherein the synthetic polymers had different degrees of neutralization from 0% to 110%.

Set-SOL-3 contains 30% gelatin to SMAc and consists of 12 3% strength solutions, with synthetic polymers having different degrees of neutralization ranging from 0% to 110%.

All complex solutions corresponding to these three groups are characterized from the point of view of viscosity and stability, in the sense that the sample is unstable if it contains insoluble phases; the sample is stable if it is a homogeneous solution without insoluble phases.

The results obtained are given in table 1 and figure 1.

Table 1: effect of the degree of neutralization of the synthetic polymer SPS and the content of natural polymer NP (type A gelatin with 200 Bloom) in the composition (SP: NP) on the solution viscosity [ eta, (cP) ] at 3% by dry weight.

It is noted from fig. 1 that the presence of natural polymers leads to a decrease in the viscosity of the synthetic polymers if the degree of neutralization of the synthetic polymers is from 30% to 60%. If the degree of neutralization is greater than 60%, the presence of the biopolymer determines an increase in the viscosity value of the composite solution.

In terms of stability of the composite solution, this depends on the degree of neutralization of the synthetic polymer. It has been noted that if the degree of neutralization of the synthetic polymer is greater than 30%, the composite system containing SMAc and gelatin is stable.

Examples 2 to 5

In these examples, the absorbency values for demineralized water (conductivity 2mS) are shown for some nonwoven fabrics: containing a density of50g/m²The viscose fibres of (1) had different degrees of impregnation with a 1 wt% concentration of polymer solution containing SMAc (described in example 1), a degree of neutralization of 59% with NaOH and various values of gelatin content, and a content of polymer composition of 1.5% by dry weight.

The experiment was carried out as follows:

a textile material having a mass of 0.5g was impregnated with the composite solution prepared according to the method described in example 1 by spraying with a laboratory device, so that a predetermined degree of impregnation IMD with respect to the dry mass of the dry textile material sample was finally obtained. Furthermore, the wet-spun sample was placed in a suspended state in an oven preheated to 180 ℃ with air circulation, and held at this temperature for 4 minutes. Finally, the sample was removed from the oven and cooled at ambient temperature. The textile material was then tested for absorbency according to the method described in the test methods section.

The experimental conditions and results are shown in table 2.

Table 2: effect of gelatin content in Polymer solution for impregnation and degree of impregnation on absorbency of impregnated nonwoven Fabric

Example numbering	[Q-tex]Water (W)	Gelatin in the complex,%)	IMD，％	Q2-texic，(g/g)	RQ1
						Example 2	9.19	7.6	8	15.79	1.71
Example 3	9.19	9.7	10	12.08	1.39
						Example 4	9.19	13.5	8	14.07	1.53
Example 5	9.19	17.6	12	15.49	1.68

Examples 6 to 12

In these examples, it is shown that a solution of synthetic polymer SMAc with a degree of neutralization of 64% (completed with NaOH), 3.6% gelatin with respect to the polymeric composite, is used on textile materials (made with a density of 50 g/m)²Of viscose) was impregnated using the same oven with air circulation as described in the previous examples, with a heat treatment at 200 c for 100 seconds, at a degree of impregnation of 20%. Finally, the simulated fluid representationVarious liquid media secreted by the human body (Margareth R.C. Marques et al, modulated Biological Fluids with a structured Application in dispensing Testing, dispensing Technologies AUGUST 2011, 1).

The results are shown in Table 3.

Table 3: effect of the composition of the liquid Medium on the absorbency of the textile Material (impregnated with a Polymer composite comprising a synthetic Polymer and gelatin)

Example 13

In this example, the temperature and time of heat treatment is shown for the relative absorption rate RQ₁In which a sample of textile material (density 50 g/m) is subjected to a heat treatment at a temperature and for a time²) Treatment is carried out to obtain an absorbent textile material.

The results are shown in FIG. 2.

The data obtained show that the heat treatment of the impregnated fabric must be carried out in such a way as to obtain the highest absorption values. The maximum is lower because of a low degree of crosslinking or because of a too high degree of crosslinking of the polymer composite.

Example 14

This example shows the effect of the type of fiber (which was impregnated into the fabric).

For this purpose, a polymer composite solution having a chemical composition in accordance with example 2 was used.

Textile materials made of polypropylene fibers (PP fibers), polyester fibers (PET fibers), Viscose fibers (Viscose-fibers) have been used.

The results are shown in FIG. 3.

Examples 15 to 16

In these examples, the effect of the type of biopolymer used to prepare the composite of the invention on the absorbency of the textile material using the preparation technique of the composite of example 1 and the method of impregnating the textile material of example 3 is shown.

Guar gum (G4129Sigma Aldrich) and soluble starch (S9765Sigma Aldrich) were used instead of gelatin.

Table 4: effect of biopolymer type (carbohydrate) on the absorbency of textile materials impregnated with Polymer composites comprising synthetic Polymer and biopolymer

Aspects of the invention

1. A polymer composite solution for treating any type of prefabricated textile material to produce a superabsorbent material. The treated material is preferably a nonwoven material.

2. The polymer solution comprises a synthetic polymer SP in salt form, a natural polymer NP and optionally additives a and water W.

3. The ratio of the preformed textile material TEX to the impregnating composition IC (═ SP + NP + a) was 85: 25 to 99: 1 (in dry weight%).

4. Ratio of synthetic polymer salt SP to natural polymer NP SP: NP was 70: 30 to 95: 5 (in dry weight percent)

5. The ratio of additive a to polymer (SP + NP) was 0.5: 5 (in dry weight%).

6. The water content of the polymer solution was 79: 99 (in wt%).

7. The synthetic polymer SP, preferably in the form of a salt, is a commercially available polymer having the following characteristics:

f) the configuration of the synthetic polymer is: linear or branched graft homopolymers or copolymers comprising a vinyl acid monomer (e.g., acrylic acid, maleic anhydride, itaconic anhydride, etc.) with or without binding to other types of vinyl monomers that do not contain carboxyl chemical functionality;

g) the total content of free carboxyl chemical functional groups is 0.009 mol/g: 0.0095mol/g to 0.01 mol/g: 0.0.15 mol/g;

h) the chemical functional group of the free carboxyl group of the synthetic copolymer SP is in the form of a salt corresponding to a degree of neutralization of from 49% to 99%, preferably from 60% to 95%, most preferably from 65% to 90%;

i) by using a strong inorganic base substance (for example, a hydroxide, bicarbonate or carbonate of lithium, sodium, potassium or ammonium, preferably a hydroxide of lithium, sodium, potassium or ammonium), a salt state of the synthetic polymer is obtained;

j) the average molecular weight of the synthetic polymer SP is from 50,000Da to 1,000,000Da, preferably from 100,000Da to 750,000Da, most preferably from 150,000Da to 500,000 Da.

8. Preferably, the natural polymer NP is a commercially available biopolymer belonging to the following classes: proteins, carbohydrates, biopolyesters or lignin (either in native form or modified by chemical or enzymatic hydrolysis); proteins and carbohydrates which are wholly water soluble are preferred and have the following properties:

a) an average molecular weight of 5,000Da to 10,000Da, preferably 25,000Da to 50,000Da, more preferably 75,000Da to 100,000 Da;

b) the free chemical functional group being NH₂、OH-CH₂、OH-C₆H_3-5(ii) a The content of the free chemical functional group is 0.001mol/g to 0.002mol/g, preferably 0.005mol/g to 0.01mol/g, as a single type or more.

9. Suitable additives a are: plasticizers, antimicrobials, active surfactants, deodorants, perfumes, preservatives, etc., in amounts related to properties other than absorbency.

10. The polymer composite solution is a stable solution that does not phase separate under storage or handling conditions.

11. Under the heat treatment condition of a temperature of 100 ℃ to 250 ℃ for 2 minutes to 20 minutes, the polymer solution can generate a three-dimensional polymer network material in a dry state by crosslinking inside the fibrous substance.

12. A method of preparing a polymer composite aqueous solution for improving the water absorption of a substrate (e.g., a fabric treated with a polymer composite), comprising the steps of:

a) preparing an alkaline alkali solution;

b) preparing an aqueous solution of the Synthetic Polymer (SP) in an acidic form, and then treating the aqueous solution of the Synthetic Polymer (SP) in an acidic form with the alkaline solution of (a) to obtain an aqueous solution of the Synthetic Polymer (SP) in a salt form at a concentration of 1 to 10 wt%, preferably 2 to 5 wt%;

c) preparing an aqueous solution of natural polymer NP at a concentration of 1 to 10 wt% (preferably 2 to 5 wt%) under heating;

d) mixing the SP solution in salt form obtained in (b) with the NP solution obtained in (c) under heating and stirring to obtain a stable polymer composite aqueous solution suitable for use as an impregnation substance to impart high water absorption to textile materials;

and optionally also,

e) adding to the composite aqueous solution obtained in (d) at least one adjunct material selected from the group consisting of plasticizers, surfactants, deodorants, perfumes and preservatives.

13. The textile material used is non-woven, woven or any other type known and commercially available in the art, formed of synthetic or natural fibres or a mixture of synthetic and natural fibres, preferably with a density of 30g/m²To 90g/m²(preferably 40 g/m)²To 80g/m²More preferably 50g/m²To 70g/m²) The synthetic fibers of (1) to form a textile material.

14. The polymer composite solution was used as a treatment agent to obtain an absorbent textile material as follows:

impregnation of the textile material using any equipment known in the art (e.g. spraying equipment, padding machines, roll coaters, reverse roll coaters, knife devices, etc.);

the treatment of the wet-spun material depends on the initial density of the material and the degree of impregnation chosen:

a) if the density of the textile material is initially higher than 70g/m²The wet textile material is first dried in a stream of hot air at a temperature of 50 ℃ to 90 ℃ (preferably 55 ℃ to 85 ℃, most preferably 60 ℃ to 80 ℃), the humidity of the solid composite material (textile + composite polymer) thus obtained being lower than 12% (preferably lower than 10% by weight, most preferably lower than 8% by weight), and then subjected to a supplementary heat treatment in a stream of hot air at a temperature of 90 ℃ to 180 ℃ (preferably 100 ℃ to 170 ℃, most preferably 110 ℃ to 160 ℃) for 5 minutes to 180 minutes (preferably 10 minutes to 150 minutes, most preferably 15 minutes to 120 minutes);

b) if the density of the textile material is initially below 70g/m²The wet woven material is then subjected to a single heat treatment at a temperature of from 100 ℃ to 150 ℃ for from 180 seconds to 300 seconds (preferably at a temperature of from 140 ℃ to 180 ℃ for from 60 seconds to 180 seconds, most preferably at a temperature of from 200 ℃ to 250 ℃ for from 30 seconds to 120 seconds).

After the heat treatment, the textile material is cooled at room temperature and finally packaged.

15. The resulting textile material has improved water absorption and can be used in a variety of applications such as cleaning wipes, household or industrial cleaning or maintenance articles, hand wipes, hand towels (which leave the user feeling that the towel is dry, but which can also absorb moisture), personal wipes, cosmetic or sanitary wipes, baby wipes, facial wipes, sanitary absorbent pads and any other similar applications.

Reference to the literature

Margareth R.C. Marques, Raimar Loebenberg and May Almukainzi, modulated Biological Fluids with a positional Application in dispensing Testing dispensing Technologies, 8.1.2011.

U.S. patent document