CN111334060A - Preparation method of bamboo fiber polylactic acid composite plastic capable of being rapidly refined and degraded - Google Patents

Abstract

The invention discloses a preparation method of a bamboo fiber polylactic acid composite plastic capable of being rapidly refined and degraded, which comprises a formula and a preparation process. The invention adopts bamboo fiber powder and polylactic acid as a formula, and prepares bamboo fiber polylactic acid composite plastic, called composite plastic for short, for producing degradable tableware by a preparation process of mixing and granulating; the technical scheme is that the bamboo fiber powder has the mechanical strength higher than that of other plant fibers, and the bamboo fiber and the polylactic acid are easily decomposed quickly under the actions of enzymolysis of microorganisms, oxidation of air, hydrolysis of rainwater and photolysis of the sun in the natural environment, so that the bamboo fiber and the polylactic acid are quickly refined, decomposed and blended into soil in the nature, and the pollution to the natural environment is reduced.

Description

A kind of preparation method of fast thinning and degrading bamboo fiber polylactic acid composite plastic

technical field

The invention relates to a thermoplastic composite plastic, in particular to a method for preparing a rapidly refined and degraded bamboo fiber polylactic acid composite plastic used for making plastic degradable tableware.

Background technique

Description: In order to alleviate the problem that disposable plastic tableware is difficult to degrade after use and causes long-term pollution to the environment, the state requires the production and use of degradable tableware; degradable tableware is one-time food boxes, knives, forks, spoons and bowls made of starch-modified plastics Plastic tableware, after the degradable tableware is used, the degradation and weathering can be accelerated under the action of microorganisms, air, water and sunlight in the natural environment; the starch-modified plastic is modified by adding edible starch to polyethylene PE resin or polypropylene PP resin. The starch-modified polyethylene PE and starch-modified polypropylene PP plastic materials are obtained; the degradation rate of the degraded tableware and the size of the weathered particle size depend on the starch content in the starch-modified plastic. The starch content is high, and the degradation rate is fast. , The weathered particle size is small; on the contrary, the starch content is small, the degradation rate is slow, and the weathered particle size is large; the production and use strength of degraded tableware is also limited by the starch content in the starch-modified plastic, and the starch content is high. The strength is low, easy to break, and the use strength is poor; on the contrary, the starch content is less, it is easy to form, the strength is high, and the use strength is good; therefore, in order to ensure that the degraded tableware is easy to make, form and use, the starch modified plastics in the prior art are added in the proportion of starch. less starch, resulting in a long degradation cycle and slow rate of starch degradation tableware products, large particle size of weathered fragments, and great pollution to the environment; starch degradation tableware degradation cycle is about ten years, and the particle size of the fragments is about 30 mm square; therefore, the prior art There are problems and shortcomings such as long degradation period, large particle size and large environmental pollution.

SUMMARY OF THE INVENTION

In view of the problems and deficiencies existing in the above-mentioned prior art, the present invention adopts bamboo fiber powder and polylactic acid as formula, and prepares a bamboo fiber polylactic acid composite plastic for producing degradable tableware through a preparation process of mixing and granulation, It is referred to as composite plastic; the use of bamboo fiber powder has higher mechanical strength than other plant fibers, and bamboo fiber and polylactic acid are easily affected by the enzymatic hydrolysis of microorganisms, the oxidation of air, the hydrolysis of rainwater, and the photolysis of the sun in the natural environment. The characteristic of rapid decomposition enables the composite plastic degradable tableware made of bamboo fiber polylactic acid composite plastic to be quickly refined and decomposed into the soil in nature after being used and discarded, so as to reduce the pollution to the natural environment. The preparation method of fiber polylactic acid composite plastic aims to make the composite plastic degradable tableware made of bamboo fiber polylactic acid composite plastic be used and discarded, and achieve the purpose of rapid degradation, particle refinement and environmental pollution reduction in the natural environment.

The object of the present invention is achieved in this way: a kind of preparation method of the bamboo fiber polylactic acid composite plastic of a kind of rapid refinement and degradation, comprises formula and preparation technology, wherein:

Described formula is bamboo fiber powder, polylactic acid, tributyl citrate and liquid paraffin, wherein:

The bamboo fiber powder is refined, dried, screened and reprocessed from bamboo fiber pulp, and the obtained particle size is 4000-5000 mesh powder;

Described polylactic acid is industrial grade polylactic acid granular plastic;

Described tributyl citrate is technical grade;

Described liquid paraffin is industrial grade;

Described preparation process is:

Step 1. Masterbatch

1.1, mixing, placing bamboo fiber powder 65%, polylactic acid 25%, tributyl citrate 8% and liquid paraffin 2% in a mixer for stirring and mixing to obtain a master mix;

1.2, granulation, use extrusion granulator to extrude and granulate the masterbatch to obtain granular masterbatch;

Step 2. Composite plastic

2.1. Mixing, placing 40% of polylactic acid, 59% of the master batch and 1% of liquid paraffin in a mixer for stirring and mixing to obtain a compound material;

2.2, granulation, use extrusion granulator to extrude and granulate the compound material to obtain a granular composite plastic composed of polylactic acid and bamboo fiber, called bamboo fiber polylactic acid composite plastic, referred to as composite plastic ;

The percentages involved in the preparation process are weight percentages.

Working principle and beneficial effects

In the composite plastics: polylactic acid acts as a binder and a molding agent, and the bamboo fiber powder acts as a reinforcing skeleton; 20% of the masterbatch is formed into a degradable plastic sheet by extrusion and rolling, and the degraded plastic sheet is then molded by blister molding to manufacture degradable tableware for fast food packaging food boxes; degradable tableware made of the composite plastic is collectively referred to as composite plastic degradable tableware ;

Since bamboo fiber powder has higher mechanical strength than other plant fibers, under the premise of satisfying injection molding, the proportion of bamboo fiber powder in composite plastics can be increased, and the mechanical strength of composite plastics can be enhanced, satisfying and enhancing the mechanical strength of composite plastics. The use strength of composite plastic degradable tableware; polylactic acid and bamboo fiber powder in composite plastic will be rapidly degraded under the action of microbial enzymolysis, air oxidation, rainfall hydrolysis, and solar photolysis in the natural environment, resulting in the use of composite plastic degradable tableware. After being abandoned, it decomposes rapidly in the natural environment. Even if it is buried in the soil without sunlight, it can be quickly decomposed by the action of microbial enzymatic hydrolysis;

Since the bamboo fiber powder can strengthen the mechanical strength of the composite plastic, the bamboo fiber powder can occupy a large proportion and a large density in the composite plastic, so that the particle size of the fragments of the composite plastic degradation tableware after being decomposed in the natural environment is small; The degradation cycle of composite plastic degradable tableware in the natural environment is 12 to 18 months, and the degradation cycle is short; the particle size of the degraded fragments is less than 1 mm square, and the fragments can be refined into the soil, reducing the pollution and damage to the natural environment and soil. .

Beneficial design development

The bamboo fiber polylactic acid composite plastic prepared by the invention can also be used to manufacture agricultural mulch film for raising seedlings and agricultural greenhouse film which are rapidly refined and degraded.

Above, the present invention adopts bamboo fiber powder and polylactic acid as a formula, and prepares a bamboo fiber polylactic acid composite plastic for producing degradable tableware through a preparation process of mixing and granulation, which is called composite plastic for short; using bamboo fiber powder It has higher mechanical strength than other plant fibers, and bamboo fiber and polylactic acid are easily decomposed by microbial enzymolysis, air oxidation, rainwater hydrolysis, and solar photolysis in the natural environment. After the composite plastic degradable tableware made of polylactic acid composite plastic is used and discarded, it is rapidly refined and decomposed into the soil in nature, so as to reduce the pollution to the natural environment. Problems and deficiencies, the provided method for preparing a rapidly refined and degraded bamboo fiber polylactic acid composite plastic enables the composite plastic degradable tableware made of the prepared bamboo fiber polylactic acid composite plastic to be used and discarded. The purpose of degradation, particle refinement, and alleviation of environmental pollution.

Example description

The following is a further detailed description of a method for preparing a fast thinning and degrading bamboo fiber polylactic acid composite plastic of the present invention through specific examples. Those skilled in the art can refer to the formulas and process methods of the examples to obtain a rapid thinning and degrading function. The bamboo fiber polylactic acid composite plastic, but should not be construed as any limitation to the present invention.

Detailed ways

Example

Name: Bamboo fiber polylactic acid composite plastic

formula:

The formula is bamboo fiber powder, polylactic acid, tributyl citrate and liquid paraffin, including:

The bamboo fiber powder is refined, dried, screened and reprocessed from bamboo fiber pulp, and the obtained particle size is 4000-5000 mesh powder;

Described polylactic acid is industrial grade polylactic acid granular plastic;

Described tributyl citrate is technical grade;

Described liquid paraffin is industrial grade;

preparation

Preparation conditions:

Ambient pressure: one atmosphere

Ambient temperature: room temperature

Preparation of main equipment: mixing mixer, extrusion granulator;

Preparation Process:

Step 1. Masterbatch

1.1, mixing, placing bamboo fiber powder 65%, polylactic acid 25%, tributyl citrate 8% and liquid paraffin 2% in a mixer for stirring and mixing to obtain a master mix;

1.2, granulation, use extrusion granulator to extrude and granulate the masterbatch to obtain granular masterbatch;

Step 2. Composite plastic

2.1. Mixing, placing 40% of polylactic acid, 59% of the master batch and 1% of liquid paraffin in a mixer for stirring and mixing to obtain a compound material;

2.2, granulation, use extrusion granulator to extrude and granulate the compound material to obtain a granular composite plastic composed of polylactic acid and bamboo fiber, called bamboo fiber polylactic acid composite plastic, referred to as composite plastic ;

The percentages involved in the preparation process are weight percentages.

Claims (1)

1. a bamboo fiber polylactic acid composite plastic preparation method of rapid refinement and degradation, comprising formula and preparation technique, is characterized in that: Described formula is bamboo fiber powder, polylactic acid, tributyl citrate and liquid paraffin, wherein: The bamboo fiber powder is refined, dried, screened and reprocessed from bamboo fiber pulp, and the obtained particle size is 4000-5000 mesh powder; Described polylactic acid is industrial grade polylactic acid granular plastic; Described tributyl citrate is technical grade; Described liquid paraffin is industrial grade; Described preparation process is: Step 1. Masterbatch 1.1, mixing, placing bamboo fiber powder 65%, polylactic acid 25%, tributyl citrate 8% and liquid paraffin 2% in a mixer for stirring and mixing to obtain a master mix; 1.2, granulation, use extrusion granulator to extrude and granulate the masterbatch to obtain granular masterbatch; Step 2. Composite plastic 2.1. Mixing, placing 40% of polylactic acid, 59% of the master batch and 1% of liquid paraffin in a mixer for stirring and mixing to obtain a compound material; 2.2, granulation, use extrusion granulator to extrude and granulate the compound material to obtain granular bamboo fiber polylactic acid composite plastic; The percentages involved in the preparation process are weight percentages.