阅读说明：本技术 一种聚烯烃编织淋膜布及其制备方法 (Polyolefin woven laminated cloth and preparation method thereof ) 是由 陆伟錩 于 2020-04-09 设计创作，主要内容包括：本发明涉及集装袋包装领域,更具体地,本发明涉及一种聚烯烃编织淋膜布及其制备方法。本发明第一个方面提供了一种聚烯烃编织淋膜布,其包括聚烯烃编织布和淋膜层；按重量份计,所述淋膜层的制备原料包括10～90份聚乙烯、10～90份聚丙烯；所述聚丙烯的熔融指数为20～40g/10min。本发明提供的聚烯烃编织淋膜布具有挺度好,复合均匀,粘结紧密,耐高温物料复合层不脱落等特点,耐高温温度可达100℃,可以满足特殊下游包装需求企业需要,相比传统集装袋,可用于高温物料灌装需求使用,在高温物料使用过程,不会造成涂层脱落,污染物料的情况。(The invention relates to the field of packaging of flexible freight bags, in particular to polyolefin woven laminated cloth and a preparation method thereof. The invention provides a polyolefin woven laminated cloth, which comprises a polyolefin woven cloth and a laminated layer; the preparation raw materials of the lamination layer comprise, by weight, 10-90 parts of polyethylene and 10-90 parts of polypropylene; the melt index of the polypropylene is 20-40 g/10 min. The polyolefin woven laminated cloth provided by the invention has the characteristics of good stiffness, uniform compounding, tight bonding, no falling of a high-temperature-resistant material compound layer and the like, can resist high temperature of 100 ℃, can meet the requirements of enterprises with special downstream packaging requirements, can be used for high-temperature material filling requirements compared with the traditional flexible freight bags, and can not cause the condition that a coating falls off and pollutes materials in the high-temperature material using process.)

1. The polyolefin woven laminated cloth is characterized by comprising polyolefin woven cloth and a laminated layer; the preparation raw materials of the lamination layer comprise, by weight, 10-90 parts of polyethylene and 10-90 parts of polypropylene; the melt index of the polypropylene is 20-40 g/10 min.

2. The polyolefin woven laminated cloth as claimed in claim 1, wherein the melt index of the polyethylene is 7-12 g/10 min.

3. The polyolefin woven laminated cloth as claimed in claim 2, wherein the density of the polyethylene is 0.91-0.93 g/cm³。

4. The polyolefin woven laminated cloth according to claim 1, wherein the preparation raw material of the laminated layer further comprises 5-30 parts by weight of an ethylene-vinyl acetate copolymer.

5. The polyolefin woven laminated cloth according to claim 4, wherein the ethylene-vinyl acetate copolymer contains 25-32 wt% of vinyl acetate; the ethylene-vinyl acetate copolymer has a melt index of 4-8 g/10 min.

6. The polyolefin woven laminated cloth according to any one of claims 1 to 5, wherein the weight of the woven cloth is 30 to 220g/m²。

7. The polyolefin woven laminated cloth according to any one of claims 1 to 5, wherein the weight of the laminated layer is 15 to 45g/m²。

8. The preparation method of the polyolefin woven laminated cloth according to any one of claims 1 to 7, which is characterized by comprising the following steps: mixing the raw materials for preparing the film coating layer by a high-temperature extruder, extruding a high-temperature film sheet by a T-shaped die head, coating the film sheet on the surface of the woven cloth, and pressing the woven cloth sheet by a rubber roller and a steel roller to obtain the film coating.

9. The method for preparing polyolefin woven laminated cloth according to claim 8, wherein the woven cloth is arranged on one side of a steel roller and the laminated layer is arranged on one side of the rubber roller when the woven cloth is pressed by the rubber roller and the steel roller.

10. The application of the polyolefin woven laminated cloth according to any one of claims 1 to 7 in a packaging bag.

Technical Field

The invention relates to the field of packaging of flexible freight bags, in particular to polyolefin woven laminated cloth and a preparation method thereof.

Background

As is known, the polyolefin production in China is mostly used for producing woven cloth of packaging materials, and most of the polyolefin production is used for producing woven bags.

For the packed objects with low requirements and large particles, the single-layer woven bags can meet the requirements, and for the packed objects with higher requirements, the packing has the performances of leakage resistance, waterproofness, temperature resistance (such as hot cement and thermokalite packing), high strength and the like.

In order to meet the requirements, double-layer bags are firstly adopted for packaging, namely, plastic film bags are arranged in the double-layer bags, and woven bags are sleeved outside the double-layer bags. The biggest defects of the double-layer bag are that the packaging operation is complex, the strength is low in the carrying process, and meanwhile, the manufacturing cost is high.

The film-coated woven bag is simple in production and can be selected to have different film thicknesses according to the requirements of packaging materials, so that the production cost is reduced, and the film-coated woven bag is popular with users.

In order to obtain a film-coated woven bag with high comprehensive performance, namely good leakage resistance, high water resistance, high strength, strong film adhesion and high temperature resistance, the selection of a proper film-forming material is very important. And the film forming material is generally a high molecular compound.

It is known that a film-forming material made of a polymer compound generally has good leakage-proof and water-proof properties. However, because the woven bag substrate polyolefin has non-polar property and the partially oxidized surface has polar property, it is difficult to find a high molecular film forming material with high adhesion to the complex surface, high strength and high temperature resistance.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a polyolefin woven laminated fabric, which comprises a polyolefin woven fabric and a laminated layer; the preparation raw materials of the lamination layer comprise, by weight, 10-90 parts of polyethylene and 10-90 parts of polypropylene; the melt index of the polypropylene is 20-40 g/10 min.

As a preferable technical scheme of the invention, the melt index of the polyethylene is 7-12 g/10 min.

As a preferable technical scheme of the invention, the density of the polyethylene is 0.91-0.93 g/cm³。

As a preferable technical scheme of the invention, the preparation raw material of the PE-coated film layer further comprises 5-30 parts by weight of ethylene-vinyl acetate copolymer.

As a preferable technical scheme of the invention, the content of vinyl acetate in the ethylene-vinyl acetate copolymer is 25-32 wt%; the ethylene-vinyl acetate copolymer has a melt index of 4-8 g/10 min.

As a preferable technical scheme of the invention, the weight of the woven cloth is 30-220 g/m²。

As a preferable technical scheme of the invention, the weight of the lamination layer is 15-45 g/m²。

The second aspect of the invention provides a preparation method of the polyolefin woven laminated cloth, which comprises the following steps: mixing the raw materials for preparing the film coating layer by a high-temperature extruder, extruding a high-temperature film sheet by a T-shaped die head, coating the film sheet on the surface of the woven cloth, and pressing the woven cloth sheet by a rubber roller and a steel roller to obtain the film coating.

As a preferable technical scheme of the invention, when the woven cloth is pressed on the steel roller through the rubber roller, the woven cloth is arranged on one side of the steel roller, and the laminating layer is arranged on one side of the rubber roller.

The third aspect of the invention provides an application of the polyolefin woven laminated cloth acrobatics packaging bag.

Compared with the prior art, the invention has the following beneficial effects:

the polyolefin woven laminated cloth provided by the invention has the characteristics of good stiffness, uniform compounding, tight bonding, no falling of a high-temperature-resistant material compound layer and the like, can resist high temperature of 100 ℃, can meet the requirements of enterprises with special downstream packaging requirements, can be used for high-temperature material filling requirements compared with the traditional flexible freight bags, and can not cause the condition that a coating falls off and pollutes materials in the high-temperature material using process.

Drawings

FIG. 1 is a schematic view of the process of coating a layer of the present invention on the surface of a woven fabric;

1-weaving cloth; 2-laminating a film layer; 3-a steel roll; 4-rubber roller

Detailed Description

The disclosure may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.

The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

In addition, the indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the number clearly indicates the singular.

The invention provides a polyolefin woven laminated cloth, which comprises a polyolefin woven cloth and a laminated layer; the preparation raw materials of the PE-coated film layer comprise, by weight, 10-90 parts of polyethylene and 10-90 parts of polypropylene.

In one embodiment, the preparation raw material of the lamination layer further comprises 5-30 parts by weight of an ethylene-vinyl acetate copolymer.

In a preferred embodiment, the preparation raw materials of the PE-coated layer comprise 40 parts by weight of polyethylene, 50 parts by weight of polypropylene and 10 parts by weight of ethylene-vinyl acetate copolymer.

Polypropylene

Polypropylene is a polymer obtained by addition polymerization of propylene.

Polypropylene, PP for short, is a colorless, odorless, nontoxic and semitransparent solid substance. Polypropylene (PP) is a thermoplastic synthetic resin with excellent performance, and is colorless translucent thermoplastic light general-purpose plastic. The polypropylene has chemical resistance, heat resistance, electrical insulation, high-strength mechanical property, good high-wear-resistance processing property and the like, so that the polypropylene can be rapidly and widely developed and applied in a plurality of fields such as machinery, automobiles, electronic and electric appliances, buildings, textiles, packaging, agriculture, forestry, fishery, food industry and the like since the coming out. In recent years, with the rapid development of the industries such as packaging, electronics, automobiles and the like in China, the development of the industries in China is greatly promoted. And because of its plasticity, polypropylene materials are gradually replacing wooden products, and the mechanical functions of metals have been gradually replaced by high strength toughness and high wear resistance. In addition, the polypropylene has good grafting and compounding functions, and has huge application space in the aspects of concrete, textile, packaging and agriculture, forestry and fishery.

In one embodiment, the polypropylene has a melt index of 20 to 40g/10 min.

Preferably, the melt index of the polypropylene is 24-32 g/10 min.

The polypropylene with the melt index of 24-32 g/10min is purchased from Shanghai Shi and is provided with the trade name of H2800.

Polyethylene

Polyethylene (PE) is a thermoplastic resin obtained by polymerizing ethylene. In industry, copolymers of ethylene with small amounts of alpha-olefins are also included.

The polyethylene resin is non-toxic and tasteless white powder or granules, is milky white in appearance, has a wax-like hand feeling, and has low water absorption rate of less than 0.01 percent. Polyethylene films are transparent and decrease with increasing crystallinity. Polyethylene films have low water permeability but high air permeability and are not suitable for freshness packaging but for moisture-proof packaging. The flame is inflammable, the oxygen index is 17.4, the flame is low in smoke during combustion, a small amount of molten drops exist, the flame is yellow on the top and blue on the bottom, and the paraffin smell exists. Polyethylene has good water resistance. The product surface is non-polar, difficult to adhere and print, and improved by surface treatment. Branched polymers are poorly resistant to photodegradation and oxidation. The molecular weight is in the range of 1 to 10 ten thousand. Ultra-high molecular weight polyethylene having a molecular weight of more than 10 ten thousand. The higher the molecular weight, the better the physical and mechanical properties, and the closer to the required level of engineering materials. However, the higher the molecular weight, the more difficult it is to process. The polyethylene has a melting point of 100-130 ℃ and excellent low-temperature resistance. The mechanical property can still be kept at-60 ℃, but the use temperature is 80-110 ℃. It is insoluble in any known solvent at normal temperature, and can be dissolved in a small amount in solvents such as toluene, amyl acetate, trichloroethylene and the like at the temperature of more than 70 ℃.

In one embodiment, the polyethylene has a melt index of 7 to 12g/10 min.

Preferably, the melt index of the polyethylene is 7-8 g/10 min; more preferably, the polyethylene has a melt index of 7g/10 min.

In one embodiment, the polyethylene has a density of 0.91 to 0.93g/cm³。

Preferably, the polyethylene has a density of 0.918g/cm³。

The melt index of the invention is 7g/10min, and the density is 0.918g/cm³The polyethylene was purchased from Yanshan petrochemical under the designation 1C 7A.

The applicant unexpectedly finds that the high-temperature resistance of the PE-coated film layer prepared by blending polypropylene with the melt index of 20-40 g/10min and polyethylene with the melt index of 6-12 g/10min is excellent. The applicant thinks that the possible reasons are that the polypropylene with the melt index of 20-40 g/10min and the polyethylene with the melt index of 6-12 g/10min have narrow molecular weight distribution, the elasticity of macromolecules and micromolecules in the molecules is close, the tape-casting property is good, meanwhile, the chain branching in the molecular structure of the polyethylene with the melt index of 6-12 g/10min is higher, the macromolecules are not closely arranged and are not regular, the crystallinity is low, the problem of poor flexibility of the film coating layer is solved, and the film coating layer and the woven cloth are more closely and uniformly compounded during film coating, so that the high temperature resistance is improved.

Ethylene-vinyl acetate copolymer

The ethylene-vinyl acetate copolymer is a general high molecular polymer, is called EVA for short, has a code of 1314, and has a molecular formula of (C2H4) x (C4H6O2) y. It is combustible and has no irritation to combustion smell.

In one embodiment, the ethylene-vinyl acetate copolymer has a vinyl acetate content of 25 to 32 wt%; the ethylene-vinyl acetate copolymer has a melt index of 4-8 g/10 min.

Preferably, the content of the vinyl acetate in the ethylene-vinyl acetate copolymer is 28 wt%; the melt index of the ethylene-vinyl acetate copolymer is 6g/10 min.

The ethylene-vinyl acetate copolymer having a vinyl acetate content of 28 wt% and a melt index of 6g/10min according to the present invention was purchased from korea under the designation VA 600.

The applicant unexpectedly finds that the ethylene-vinyl acetate copolymer is added into the laminated film layer, the content of vinyl acetate in the ethylene-vinyl acetate copolymer is 25-32 wt%, the melt index is 4-8 g/10min, and when the weight of the ethylene-vinyl acetate copolymer is 5-30 parts, the hand feeling of the woven cloth can be improved, the applicant considers that the possible reason is that certain vinyl acetate in the ethylene-vinyl acetate copolymer has reduced crystallinity, the regularity of molecules between polypropylene and polyethylene in the laminated film layer is damaged, the flexibility of the laminated film layer is improved, the hand feeling is better, the melt index is close to that of polyethylene, the polyethylene is good in compatibility, the ethylene-vinyl acetate copolymer and the polyethylene play a synergistic role, the tape-casting property during film coating is further improved, and the hardness difference brought to the laminated film layer by the polypropylene is improved, poor hand feeling.

In one embodiment, the weight of the woven cloth is 30-220 g/m²。

The woven cloth is made of polypropylene, polyethylene or other polyolefin materials.

In one embodiment, the weight of the laminated film layer is 15-45 g/m²。

The weights of the woven cloth and the laminated cloth according to the invention can be selected routinely by the person skilled in the art according to the weights given in the present invention.

The test condition of the melt index of the invention is 190 ℃ and 2.16 Kg.

The test condition for the density according to the present invention was 23 ℃.

The second invention of the invention provides a preparation method of polyolefin woven laminated cloth, which comprises the following steps: mixing the raw materials for preparing the film coating layer by a high-temperature extruder, extruding a high-temperature film sheet by a T-shaped die head, coating the film sheet on the surface of the woven cloth, and pressing the woven cloth sheet by a rubber roller and a steel roller to obtain the film coating.

In one embodiment, the method for preparing the polyolefin woven laminated cloth comprises the following steps: mixing the preparation raw materials of the film coating layer by a high-temperature extruder, extruding a high-temperature sheet film by a T-shaped die head, coating the high-temperature sheet film on the surface of woven cloth, wherein the woven cloth is arranged on one side of a steel roller, and the film coating layer is arranged on one side of a rubber roller, and laminating to obtain the composite material.

As shown in fig. 1, when the lamination layer is coated on the surface of the woven fabric, the lamination layer 2 is arranged on the side of the rubber roller 4, and the woven fabric 1 is arranged on the side of the steel roller 3.

The polypropylene and the polyethylene are added into the spraying film layer, the melt flow rate of the spraying film layer fluctuates greatly, the traditional woven cloth and the spraying film layer are compounded, the coating process is unstable, the obtained adhesion strength of the spraying film layer and the woven cloth is reduced, and the spraying film layer falls off from the surface of the woven cloth and pollutes materials in the using process. This applicant discovers unexpectedly, when through rubber roller and steel roll pressfitting, weaves the cloth and in steel roll one side, drenches the rete in rubber roller one side for it is showing the improvement to drench the rete and weave the adhesion strength between the cloth, has avoided in the use, drenches the problem of rete contaminated material. The applicant thinks that the probable reason is to be located steel roller one side with the cloth of weaving, drench the rete and be located rubber roller one side, at the in-process of pressfitting, the specific surface area of the contact between drench rete and the cloth of weaving is bigger, drench the rete can permeate the cloth of weaving surface for drench the rete adhesion more even, the bonding is inseparable, in the use, the adhesion of drenching the rete and the cloth of weaving is greater than the adhesion of material and drenching the rete, can not cause the condition that drenching the rete and drop from the cloth of weaving surface in the use of woven cloth, the.

The invention provides an application of polyolefin woven laminated cloth in a packaging bag.

Flexible container: the flexible container bag is also called flexible container bag, ton bag, space bag, etc. the FIBC is one kind of container unit, and may be transported in container unit by crane or fork truck. The flexible container is widely used for transporting and packaging powdery, granular and blocky articles such as food, grain, medicine, chemical industry, mineral products and the like, and is generally used as a packaging product for transportation and storage in developed countries.