阅读说明：本技术 一种薄膜级淀粉基复合材料及其制备方法 (Film-grade starch-based composite material and preparation method thereof ) 是由 曾广胜 江太君 陈一 孟聪 胡灿 尹琛 刘水长 于 2019-11-29 设计创作，主要内容包括：本发明公开了一种薄膜级淀粉基复合材料及其制备方法,由以下质量份数的原材料组成：淀粉：20~50份、增塑剂：4~10份、聚烯烃塑料：40~70份、润滑剂：2~5份、开口剂：0.5~2份、抗氧剂：0.3~1份。本发明采用乙烯-丙烯酸丁酯对玉米淀粉进行增塑与相容改性制备薄膜级高填充淀粉基复合材料,复合材料的吸膜过程稳定,力学性能好。(The invention discloses a film-grade starch-based composite material and a preparation method thereof, wherein the film-grade starch-based composite material is prepared from the following raw materials in parts by mass: starch: 20-50 parts of a plasticizer: 4-10 parts of polyolefin plastic: 40-70 parts of lubricant: 2-5 parts of an opening agent: 0.5-2 parts of antioxidant: 0.3-1 part. The invention adopts ethylene-butyl acrylate to plasticize and compatibly modify corn starch to prepare the thin-film high-filling starch-based composite material, and the composite material has stable film absorption process and good mechanical property.)

1. The film-grade starch-based composite material is characterized by comprising the following raw materials in parts by mass: starch: 20-50 parts of a plasticizer: 4-10 parts of polyolefin plastic: 40-70 parts of lubricant: 2-5 parts of an opening agent: 0.5-2 parts of antioxidant: 0.3-1 part.

2. The film-grade starch-based composite material according to claim 1, wherein the starch is native unmodified corn starch or tapioca starch.

3. The film-grade starch-based composite material according to claim 2, wherein the starch has a particle size of 60-100 mesh and a water content of less than 10%.

4. The film-grade starch-based composite material according to claim 1, wherein the plasticizer is ethylene butyl acrylate having an ester content of greater than 30%.

5. The film-grade starch-based composite material of claim 1, wherein the lubricant is at least one of polyethylene wax and stearic acid.

6. The film-grade starch-based composite material of claim 1, wherein the opening agent is at least one of talc or oleamide.

7. The film-grade starch-based composite material according to claim 1, wherein the polyolefin plastic is at least one of low density polyethylene and metallocene polyethylene.

8. The film-grade starch-based composite of claim 1, wherein the antioxidant is at least one of 1010, 1076.

9. A method for preparing a film-grade starch-based composite material according to any one of claims 1 to 8, comprising the steps of:

s1, putting starch and a plasticizer into a high-speed mixer, uniformly mixing, adding other raw materials, and uniformly mixing;

s2, putting the mixture obtained in the step S1 into a parallel double-screw extruder for extrusion and granulation.

10. The method as claimed in claim 9, wherein the temperature of the parallel twin-screw extruder in step S2 is set from blanking to die as: 150-160-165-170-180-170-175-170 ℃.

Technical Field

The invention relates to the technical field of starch-based materials, in particular to a film-grade starch-based composite material and a preparation method thereof.

Background

Starch is a renewable recyclable green material from natural plants, can be used as grain for human use, and is widely applied to the fields of chemical industry and new materials for preparing various composite materials. Due to the excellent biodegradability, starch is generally used as filling to prepare thermoplastic high-biochar-content bio-based composite materials, is widely applied to disposable products, and is more and more valued by people in the large environment that petrochemical resources are increasingly in shortage and white pollution is increasingly serious at present. The film is a sheet material with one thickness prepared by various different processes by utilizing high polymer materials, and is widely applied to the field of packaging due to excellent flexibility, transparency and strong toughness.

At present, most plastic films on the market are processed and produced by using petroleum-based plastics as raw materials, and most of the films are non-degradable materials. With the shortage of petrochemical resources and the growing concern of white waste, more and more enterprises turn the traditional petroleum-based raw materials into fully-degradable materials. Starch is increasingly used as a pure natural resource for preparing fully degradable materials and disposable products, and most of the products can be rapidly degraded under natural conditions, converted into water and carbon dioxide and returned to the nature. However, the simple starch has large hydrogen bonding effect, so that the material has a flowing temperature higher than a decomposition temperature, cannot be molded, and the starch needs to be modified and plasticized for manufacturing products.

Disclosure of Invention

The invention aims to provide a film-grade starch-based composite material which has good mechanical property and stable film absorption process aiming at the defects in the prior art.

The invention aims to provide a preparation method of the film-grade starch-based composite material.

The purpose of the invention is realized by the following technical scheme:

a film-grade starch-based composite material is composed of the following raw materials in parts by mass: starch: 20-50 parts of a plasticizer: 4-10 parts of polyolefin plastic: 40-70 parts of lubricant: 2-5 parts of an opening agent: 0.5-2 parts of antioxidant: 0.3-1 part.

Further, the starch is natural unmodified corn starch or tapioca starch.

Further, the particle size of the starch is 60-100 meshes, and the water content of the starch is lower than 10%.

Further, the plasticizer is ethylene-butyl acrylate with an ester content of more than 30%.

Further, the lubricant is at least one of polyethylene wax and stearic acid.

Further, the opening agent is at least one of talcum powder or oleamide.

Further, the polyolefin plastic is at least one of low density polyethylene and metallocene polyethylene.

Further, the antioxidant is at least one of 1010 and 1076.

The preparation method of the film-grade starch-based composite material comprises the following steps:

s1, putting starch and a plasticizer into a high-speed mixer, uniformly mixing, adding other raw materials, and uniformly mixing;

s2, putting the mixture obtained in the step S1 into a parallel double-screw extruder for extrusion and granulation.

Further, the temperature of the parallel twin-screw extruder in step S2 is set from blanking to die as follows: 150-160-165-170-180-170-175-170 ℃.

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

the invention adopts ethylene-butyl acrylate to plasticize and compatibly modify corn starch to prepare the thin-film high-filling starch-based composite material, and the composite material has stable film absorption process and good mechanical property.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the following specific examples.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.