阅读说明：本技术 一种可降解材料及其制备方法 (Degradable material and preparation method thereof ) 是由 唐念彬 唐豪 于 2020-12-26 设计创作，主要内容包括：本发明公开了一种可降解材料及其制备方法,其原料按重量份包括稻草秸秆纤维5-5.5份、椰子纤维4.5-6.3份、玉米交联淀粉3.2-4份、高密度聚乙烯8.4-9.5份、聚乙烯醇-羧甲基纤维素3.3-3.9份、高岭土3-4份、海泡石3-4份、碳酸钙2-3份、增塑剂4-5份、光敏剂6.2-8.7份和偶联剂8.2-10.5份。通过在材料中设置了稻草秸秆纤维、椰子纤维和玉米交联淀粉这类植物纤维,使得在埋入土壤中时可以更加容易地被分解,同时还增加了高岭土,海泡石和碳酸钙等天然矿物质以改善可降解材料的强度,并通过偶联剂、光敏剂和增塑剂以增加材料的塑性和粘接强度,使得具备生活中使用时必要的强度和塑性,从而在可降解的同时,还具备了较好的强度,使得可以更加耐用。(The invention discloses a degradable material and a preparation method thereof, and the degradable material comprises, by weight, 5-5.5 parts of straw stalk fiber, 4.5-6.3 parts of coconut fiber, 3.2-4 parts of corn crosslinked starch, 8.4-9.5 parts of high-density polyethylene, 3.3-3.9 parts of polyvinyl alcohol-carboxymethyl cellulose, 3-4 parts of kaolin, 3-4 parts of sepiolite, 2-3 parts of calcium carbonate, 4-5 parts of plasticizer, 6.2-8.7 parts of photosensitizer and 8.2-10.5 parts of coupling agent. The material is provided with plant fibers such as straw stalk fibers, coconut fibers and corn crosslinked starch, so that the material can be decomposed more easily when being buried in soil, natural mineral substances such as kaolin, sepiolite and calcium carbonate are added to improve the strength of the degradable material, and a coupling agent, a photosensitizer and a plasticizer are used to increase the plasticity and bonding strength of the material, so that the material has the strength and plasticity necessary for use in life, and the material is degradable and has better strength, so that the material can be more durable.)

1. A degradable material is characterized in that,

the raw materials of the composite material comprise, by weight, 5-5.5 parts of straw stalk fiber, 4.5-6.3 parts of coconut fiber, 3.2-4 parts of corn crosslinked starch, 8.4-9.5 parts of high-density polyethylene, 3.3-3.9 parts of polyvinyl alcohol-carboxymethyl cellulose, 3-4 parts of kaolin, 3-4 parts of sepiolite, 2-3 parts of calcium carbonate, 4-5 parts of a plasticizer, 6.2-8.7 parts of a photosensitizer and 8.2-10.5 parts of a coupling agent.

2. The degradable material of claim 1,

the plasticizer includes dioctyl phthalate, dicyclohexyl phthalate, and diisobutyl phthalate.

3. The degradable material of claim 1,

the photosensitizer comprises aromatic ketones, benzoin ethers, azo compounds and organic sulfides.

4. A method for preparing a degradable material is characterized in that,

the method comprises the following steps: preparing straw stalk fiber and coconut fiber;

adding straw stalk fiber and coconut fiber into a coupling agent and stirring to obtain a first mixed solution;

adding the corn crosslinked starch and the polyvinyl alcohol-carboxymethyl cellulose into the first mixed solution, stirring, standing, filtering and precipitating to obtain a second mixed solution;

sequentially adding calcium carbonate, high-density polyethylene, kaolin and sepiolite into the second mixed solution, heating and continuously stirring, and cooling to obtain a third mixed solution;

adding a plasticizer and a photosensitizer into the third mixed solution, and continuously stirring to obtain a fourth mixed solution;

and adding the fourth mixed solution into a screw extruder to extrude, and obtaining the degradable plastic material.

5. The method for preparing degradable material according to claim 4,

the method for preparing the straw stalk fiber and the coconut fiber comprises the following specific steps:

putting the straws into water, stirring and cleaning, and removing precipitates;

crushing the straws by using a crusher to obtain crude fibers;

the crude fiber is frozen to the internal moisture and frozen, then is unfrozen and processed into fine fiber by a fiber machine.

6. The method for preparing degradable material according to claim 4,

the concrete steps of adding the fourth mixed solution into a screw extruder to extrude and obtain the degradable plastic material are as follows:

adding the fourth mixed solution into a screw extruder;

setting the five-section heating temperature as 118-120, 120-123 ℃, 123-126 ℃, 126-130 ℃ and 130-135 ℃ in sequence, and the screw rotation speed as 20-25 rpm;

starting the screw extruder to extrude the degradable material;

and cooling the degradable material.

7. The method for preparing degradable material according to claim 6,

the heating temperature of the five sections is 119 ℃, 122 ℃, 124 ℃, 126 ℃ and 131 ℃ in sequence.

8. The method for preparing degradable material according to claim 6,

the degradable material is cooled by air cooling and direct blowing.

Technical Field

The invention relates to the technical field of materials, in particular to a degradable material and a preparation method thereof.

Background

While creating modern civilization, mankind also has a negative impact-white pollution. Disposable tableware, disposable plastic products, agricultural mulching films and the like are difficult to recycle, and the treatment method mainly comprises incineration and burying. A large amount of harmful gas is generated by burning, so that the environment is polluted; if buried, the polymer in the buried polymer cannot be degraded by microorganisms in a short time and pollutes the environment. The residual plastic film exists in the soil, which hinders the development of crop roots and the absorption of water and nutrients, so that the air permeability of the soil is reduced, and the yield of crops is reduced; after the animals eat the residual plastic film, the animals can cause intestinal obstruction and die; synthetic fiber fishing nets and fishing lines lost to or discarded in the ocean have caused considerable damage to marine life, and thus it is imperative to promote green consumption and enhance environmental protection. In the face of increasingly depleted petroleum resources, biodegradable materials conforming to trends are becoming a research and development hotspot as high-tech products and environment-friendly products.

The existing degradable material is not enough in strength and damages in the using process while meeting the requirement of degradability, so that the use is inconvenient and the popularization is inconvenient.

Disclosure of Invention

The invention aims to provide a degradable material and a preparation method thereof, and aims to solve the problem that the existing material is not enough in strength and easy to damage while being degradable.

In order to realize the purpose, the invention provides a degradable material, which comprises the following raw materials, by weight, 5-5.5 parts of straw stalk fiber, 4.5-6.3 parts of coconut fiber, 3.2-4 parts of corn crosslinked starch, 8.4-9.5 parts of high-density polyethylene, 3.3-3.9 parts of polyvinyl alcohol-carboxymethyl cellulose, 3-4 parts of kaolin, 3-4 parts of sepiolite, 2-3 parts of calcium carbonate, 4-5 parts of a plasticizer, 6.2-8.7 parts of a photosensitizer and 8.2-10.5 parts of a coupling agent.

Wherein the plasticizer comprises dioctyl phthalate, dicyclohexyl phthalate and diisobutyl phthalate.

Wherein the photosensitizer comprises aromatic ketones, benzoin ethers, azo compounds and organic sulfides.

In a second aspect, the present invention also provides a method for preparing a degradable material, comprising: preparing straw stalk fiber and coconut fiber; adding straw stalk fiber and coconut fiber into a coupling agent and stirring to obtain a first mixed solution; adding the corn crosslinked starch and the polyvinyl alcohol-carboxymethyl cellulose into the first mixed solution, stirring, standing, filtering and precipitating to obtain a second mixed solution; sequentially adding calcium carbonate, high-density polyethylene, kaolin and sepiolite into the second mixed solution, heating and continuously stirring, and cooling to obtain a third mixed solution; adding a plasticizer and a photosensitizer into the third mixed solution, and continuously stirring to obtain a fourth mixed solution; and adding the fourth mixed solution into a screw extruder to extrude, and obtaining the degradable plastic material.

Wherein the specific steps for preparing the straw stalk fiber and the coconut fiber are as follows: putting the straws into water, stirring and cleaning, and removing precipitates; crushing the straws by using a crusher to obtain crude fibers; the crude fiber is frozen to the internal moisture and frozen, then is unfrozen and processed into fine fiber by a fiber machine.

The specific steps of adding the fourth mixed solution into a screw extruder to extrude and obtain the degradable plastic material are as follows: adding the fourth mixed solution into a screw extruder; setting the five-section heating temperature as 118-120, 120-123 ℃, 123-126 ℃, 126-130 ℃ and 130-135 ℃ in sequence, and the screw rotation speed as 20-25 rpm; starting the screw extruder to extrude the degradable material; and cooling the degradable material.

Wherein the heating temperatures of the five sections are 119 ℃, 122 ℃, 124 ℃, 126 ℃ and 131 ℃ in sequence.

Wherein, the degradable material is cooled by air cooling and direct blowing.

The invention relates to a degradable material and a preparation method thereof, and the degradable material comprises, by weight, 5-5.5 parts of straw stalk fiber, 4.5-6.3 parts of coconut fiber, 3.2-4 parts of corn crosslinked starch, 8.4-9.5 parts of high-density polyethylene, 3.3-3.9 parts of polyvinyl alcohol-carboxymethyl cellulose, 3-4 parts of kaolin, 3-4 parts of sepiolite, 2-3 parts of calcium carbonate, 4-5 parts of plasticizer, 6.2-8.7 parts of photosensitizer and 8.2-10.5 parts of coupling agent. Through setting up straw stalk fibre, coconut fiber and maize crosslinked starch this kind of plant fiber in the material, make can be decomposed more easily when burying in soil, still added the plasticity that a small amount of high density polyethylene improved degradable material, still increased kaolin simultaneously, natural mineral matters such as sepiolite and calcium carbonate are in order to improve degradable material's intensity, and through coupling agent, photosensitizer and plasticizer in order to increase material's plasticity and adhesive strength, make necessary intensity and plasticity when possessing the life, thereby in the degradable, still possessed better intensity, make and to be more durable, thereby solved current material and intensity problem easy damage inadequately in the degradable.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a flow chart of a method for preparing a degradable material according to the invention;

FIG. 2 is a flow chart of the present invention for preparing rice straw fiber and coconut fiber;

FIG. 3 is a flow chart of adding cross-linked corn starch and PVA-CMC to the first mixture, stirring, standing, filtering, and precipitating to obtain a second mixture;

FIG. 4 is a flow chart of a third mixed solution obtained by sequentially adding calcium carbonate, high density polyethylene, kaolin and sepiolite to the second mixed solution, heating and continuously stirring, and cooling according to the present invention;

FIG. 5 is a flow chart of the present invention for adding the fourth mixed solution into the screw extruder to extrude and obtain the degradable plastic material;

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

On one hand, the invention provides a degradable material, which comprises the following raw materials in parts by weight:

5-5.5 parts of straw stalk fiber, 4.5-6.3 parts of coconut fiber, 3.2-4 parts of corn crosslinked starch, 8.4-9.5 parts of high-density polyethylene, 3.3-3.9 parts of polyvinyl alcohol-carboxymethyl cellulose, 3-4 parts of kaolin, 3-4 parts of sepiolite, 2-3 parts of calcium carbonate, 4-5 parts of plasticizer, 6.2-8.7 parts of photosensitizer and 8.2-10.5 parts of coupling agent.

In the embodiment, plant fibers such as straw stalk fibers, coconut fibers and corn crosslinked starch are arranged in the material, so that the material can be more easily decomposed when being buried in soil, a small amount of high-density polyethylene is added to improve the plasticity of the degradable material, natural mineral substances such as kaolin, sepiolite and calcium carbonate are added to improve the strength of the degradable material, and a coupling agent, a photosensitizer and a plasticizer are used to improve the plasticity and the bonding strength of the material, so that the material has the strength and the plasticity necessary for use in life, and the material can be degraded, has better strength and can be more durable, and the problem that the strength of the existing material is not enough and is easily damaged is solved.

In a second aspect, referring to fig. 1, the present invention further provides a method for preparing a degradable material, including:

s101, preparing straw stalk fibers and coconut fibers;

referring to fig. 2, the specific steps are:

s201, putting straws into water, stirring and cleaning, and removing precipitates;

the collected straws contain impurities such as soil and dust, which reduce the performance of fibers if processed together with the straws, so that the straws need to be put into a cleaning machine in advance for cleaning, and the impurities are removed as much as possible.

S202, crushing the straws by using a crusher to obtain crude fibers;

the cleaned straws can be crushed by a crusher, the crusher is a machine with a rotary blade, and the straws and clean water are poured into the crusher together to be quickly cut into thin flaky crude fibers.

S203, the crude fiber is frozen until the internal water is frozen, and then the frozen crude fiber is unfrozen and processed into fine fiber by a fiber machine.

The low-temperature brittleness of the material is utilized, namely the hardness and the brittleness of the material are increased along with the reduction of the temperature, and the plasticity and the toughness are reduced, so that the coarse fibers can be more easily broken into the fine fibers by a fiber machine after the material is unfrozen.

S102, adding straw stalk fibers and coconut fibers into a coupling agent and stirring to obtain a first mixed solution;

the coupling agent is a plastic additive that improves the interfacial properties of synthetic resins and inorganic fillers or reinforcing materials in plastic compounding. Also known as surface modifiers. It can reduce the viscosity of synthetic resin melt in the course of plastic processing, and can improve the dispersity of filling agent to raise processing property, so that it can make the product obtain good surface quality and mechanical, thermal and electric properties. The coupling agent selected here is a silane coupling agent, which can improve the adhesive property of the straw stalk fiber and the coconut fiber, thereby improving the strength of the straw stalk fiber and the coconut fiber, and the straw stalk fiber and the coconut fiber have good degradability because of being biological fiber, so that the straw stalk fiber and the coconut fiber can be degraded more conveniently and easily.

S103, adding the cross-linked corn starch and the polyvinyl alcohol-carboxymethyl cellulose into the first mixed solution, stirring, standing, filtering and precipitating to obtain a second mixed solution;

referring to fig. 3, the specific steps are:

s301, adding the corn crosslinked starch into the first mixed solution, and stirring for 10 min;

the cross-linked starch can be prepared by the cross-linking reaction of the corn starch and the epichlorohydrin, the acid resistance, the shearing resistance and the ageing resistance of the starch are improved to a great extent by the original corn starch after cross-linking, the stability of the starch is improved, the corn cross-linked starch can be filled in gaps among fibers, the strength of the material is increased, and the material can be degraded.

S302, adding polyvinyl alcohol-carboxymethyl cellulose, and stirring for 20 min;

the polyvinyl alcohol-carboxymethyl cellulose has the functions of thickening, film forming, adhesion, water retention, colloid protection, emulsification, suspension and the like, and can improve and further enhance the adhesive property of the material, so that the components can be combined more tightly.

S303 is left to stand for 15min and the precipitate is filtered.

After addition of these substances, there are precipitates which are partly due to reaction of the impurities or to insufficient agitation, which further processing can affect the properties of the material, and which therefore need to be filtered.

S104, sequentially adding calcium carbonate, high-density polyethylene, kaolin and sepiolite into the second mixed solution, heating and continuously stirring, and cooling to obtain a third mixed solution;

referring to fig. 4, the specific steps are:

s401, sequentially adding calcium carbonate and high-density polyethylene into the second mixed solution, heating to 160-170 ℃, and stirring for 10 min;

the high-density polyethylene (HDPE) is a white powder or granular product, is nontoxic and tasteless, has the crystallinity of 80-90 percent, the softening point of 125-l 35 ℃, and the use temperature of 100 ℃; the hardness, tensile strength and creep property are better than those of low-density polyethylene; the material has better wear resistance, electrical insulation, toughness and cold resistance, can increase the toughness of the material, is in a molten state at 160-170 degrees, and can be more fully mixed. Calcium carbonate is light calcium carbonate, and a filler as a material is added to further increase the strength of the material.

S402, standing for 10-20min to reduce the temperature to below 50 ℃;

and S403, adding kaolin and sepiolite, and stirring for 25-30 min.

The kaolin is a non-metal mineral product, is clay and claystone which mainly comprise kaolinite clay minerals, and has good physical and chemical properties such as plasticity, fire resistance and the like; sepiolite is a fibrous hydrous magnesium silicate, generally has white, light grey, light yellow and other colors, is opaque and not glossy, is soft when meeting water, becomes hard when disturbed,

s105, adding a plasticizer and a photosensitizer into the third mixed solution, and continuously stirring to obtain a fourth mixed solution;

the plasticizer includes dioctyl phthalate, dicyclohexyl phthalate, and diisobutyl phthalate. The photosensitizer comprises aromatic ketones, benzoin ethers, azo compounds and organic sulfides. Photosensitizers are substances that transfer light energy to some reactant that is not sensitive to visible light to increase or broaden the light sensitivity, thereby allowing accelerated decomposition under light conditions.

S106, adding the fourth mixed solution into a screw extruder to extrude, and obtaining the degradable plastic material.

Referring to fig. 5, the specific steps are:

s501, adding the fourth mixed solution into a screw extruder;

the extruder belongs to one of the types of plastic machinery, and can divide a machine head into a right-angle machine head, an oblique-angle machine head and the like according to the material flow direction of the machine head and the included angle of the central line of a screw. The screw extruder depends on the pressure and the shearing force generated by the rotation of the screw, so that materials can be fully plasticized and uniformly mixed and are molded through a neck mold.

S502, setting the five-section heating temperature to be 118-120, 120-123 ℃, 123-126 ℃, 126-130 ℃ and 130-135 ℃ in sequence, and setting the screw rotation speed to be 20-25 rpm;

the fourth mixed liquid can be heated more uniformly by a five-stage stepped heating mode of the screw extruder.

S503, starting a screw extruder to extrude the degradable material;

s504, cooling the degradable material.

And finally, extruding to obtain a degradable material, and cooling the material to the normal temperature in an air cooling mode for use.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.