WO2016061904A1

WO2016061904A1 - Controllable rapid degradable plastic and preparation method therefor

Info

Publication number: WO2016061904A1
Application number: PCT/CN2015/000702
Authority: WO
Inventors: 赵长军; 魏铁军
Original assignee: 赵长军; 魏铁军
Priority date: 2014-10-22
Filing date: 2015-10-19
Publication date: 2016-04-28
Also published as: CN104356463B; CN104356463A

Abstract

The present invention relates to a controllable rapid degradable plastic and preparation method therefor. The controllable rapid degradable plastic is made from the following raw materials in weight percentage: yeast 1-5%, rapid degradation agent 0.1-0.5%, ash 0-5%, corn starch 2-10%, calcium carbonate 10-50%, defoamer 1-2%, color masterbatch 0-0.5%, and balance of polyethylene or polypropylene. The respective raw materials are mixed, crushed, and granulated. The obtained particles are dried via infrared. Then the dried particles are stirred, heated, and molded by blowing molding, extrusion molding or compression molding. Then the molded film is cooled, blank pressed and made into bags. The degradation time of the inventive product can be controlled by adjusting the proportions of ash, corn starch, calcium carbonate, yeast, and rapid degradation agent. The degradation time is in a range of 3 months to 5 years.

Description

Controllable rapid degradation plastic and preparation method thereof

Technical field

The invention relates to the preparation of a degradable plastic and belongs to the technical field of materials.

Background technique

Degradable plastics are generally considered to be plastics that can be decomposed into low molecular weight by sunlight radiation or microorganisms in the soil. In addition to being degradable, they should also have properties that are easy to process and meet the requirements of use. The harmful effect of sunlight on polymer materials is the combined effect of ultraviolet light and oxygen, so it is called photooxidative degradation. In the case of polyolefins, photooxidation often causes chain scission or cross-linking of the polymer with concomitant formation of some oxygen-containing functional groups such as ketones, carboxylic acids, peroxides and alcohols. Its degradation mainly comes from the catalyst residues in the polymer, as well as the initiation of peroxide and carbonyl introduced during processing. The research of degradable plastics is just right for adapting to China's sustainable development strategy, and can adapt to the development of society. The use of polymer materials for chemical and biological methods to synthesize light/biodegradable plastics is the main direction of our research and development. We can use these polymer synthesis methods to synthesize the materials we need - degradable plastics.

The types of degradable plastics are photodegradable plastics, biodegradable plastics, and light/biodouble degradable plastics. Fully biodegradable plastics with complete degradation characteristics and photo/biodegradable plastics with dual degradation characteristics are the main research directions.

Although there are many researches and reports on degradable plastics, many specific problems cannot be solved. The promotion is extremely difficult and the prospects are not optimistic. The reason is (1) the color of the degradable plastic bag is dull and yellow, and the transparency is low, giving a feeling of being not clean and ugly, and it is not safe to use. In addition, the degradable plastic bag has low load-bearing capacity and cannot meet the requirements of customers for more loading and repeated use; (2) the price is higher, the degradable plastic is 15% higher than the price of the current plastic products, and the high degradation can be completely eliminated. 8 times. The degraded polypropylene snack box promoted on the railway in China is 50% to 80% higher than the original polystyrene foam fast food box. As for the agricultural film, the current plastic film has a variety of ultra-thin film, the specifications can be as thin as 0.004 ~ 0008mm, so only cover 1 ~ 2kg per acre, and starch due to large molecular size and related process problems, made The thickness of the mulch film is generally above 0.02 mm, and the coverage per acre is several times higher than that of the current plastic film, resulting in high use cost. (3) Performance. The mechanical properties of various brands of starch plastics published at home and abroad can generally be compared with the current plastics of similar applications, but their performance is often unsatisfactory. One of the main drawbacks is that the degradation resistance of starch-containing degradation plastics is not good, wet strength. Poor, in the case of water, the mechanical properties are greatly reduced, and the water resistance is precisely the advantage of the current plastics in the process of use. In addition, in terms of economy, in the production of degradable plastic products, it is often necessary to add different additives such as a degrading agent, a stabilizer, a plasticizer, a processing aid, a coloring agent and the like. These additives are gradually released into the natural environment as the plastic degradation process, and whether there is an impact on the environment and the environmental impact or potential impact of the products and residues in the degradation process, there is still no deep and long-term follow-up study. In addition, the application research of degradable plastics is not synchronized with product development. In practice, the application tracking research is not paid enough attention, so there is a lack of system accumulation. The evaluation data is not conducive to the development of the market. Among the degradable plastics currently developed in China, except for fully biodegradable plastics, plastics cannot be completely degraded in a short period of time. Its own technology, such as more reasonable process formula, more perfect, more advanced molding technology and equipment, accurate time control, rapid degradation after use and complete degradation, and recycling technology of scraps need to be further improved and improved. .

Patent CN 103467814 A discloses a formulation and a manufacturing process of a degradable plastic bag with adjustable degradation time; it comprises 65-80% calcium carbonate powder, 1-3% inorganic powder, 1-3% high filling powder and 14 - 35% polyethylene; wherein the calcium carbonate powder consists of 80% calcium carbonate particles, 15% ductile particles, 2% antifoaming agent and 3% filler particles. This technology contains a large amount of filler powder, and the degradation efficiency and product quality need to be improved.

Summary of the invention

The object of the present invention is to overcome the above-mentioned deficiencies and to provide a controllable rapid degradation plastic and a preparation method thereof, which have good chemical and biodegradability and good controllability of degradation.

The technical solution adopted by the invention is:

A controllable rapid degradation plastic made from the following weight percentages of raw materials: yeast 1-5%, rapid degradation agent 0.1-0.5%, volcanic ash 0-5%, corn starch 2-10%, calcium carbonate 10-50% , defoamer 1-2%, color masterbatch 0-0.5%, balance polyethylene or polypropylene.

The controllable rapid degradation plastic is preferably made of the following weight percentages of raw materials: yeast 1-3%, rapid degradation agent 0.1-0.5%, pozzolan 3-5%, corn starch 2-10%, calcium carbonate 10- 50%, defoamer 1-2%, color masterbatch 0.1-0.5%, balance polyethylene or polypropylene.

The controllable rapid degradation plastic is further preferably made of the following raw materials by weight: yeast 2%, rapid degradation agent 0.1%, volcanic ash 3%, corn starch 5%, calcium carbonate 20%, defoaming agent 2%, Color masterbatch 0.5%, balance polyethylene or polypropylene.

The rapid degradation agent is a d ₂ w or d ₃ w degrading agent.

The preparation method of the above controllable rapid degradation plastic comprises the following steps:

(1) mixing and pulverizing each raw material, granulating, and drying the granules under infrared;

(2) stirring the particles after drying, holding at 120-140 ° C for 1-2 hours, and then heating and extruding blown film forming;

(3) Cooling, crimping the formed film and making a bag.

The beneficial effects of the present invention over the prior art are:

The rapid degradation agent used in the invention is first oxidatively degraded, and then biodegraded. During the oxidative degradation process, the d ₂ w continuously touches the CH bond in the plastic, and the plastic is first broken into pieces. d ₂ w continues to act to break the material from the polymer into a substance having a molecular weight of less than 5000 Daltons. And the degradation of plastic begins to degrade after the shelf life, and the rate of degradation has a certain relationship with the external conditions. Yeast is involved in biodegradation, and combined with rapid degradation agents can reduce degradation conditions and accelerate degradation. Volcanic ash can also be activated to accelerate degradation.

The product prepared by the invention can control the degradation time by controlling the proportion of pozzolan, corn starch, calcium carbonate, yeast and rapid degradation agent, and the degradation time ranges from 3 months to 5 years. The degradation conditions are simple, under ultraviolet light, normal temperature, humidity of 3-50 degrees. After degradation, the plastic is broken, like gray.

DRAWINGS

Figure 1 shows the surface morphology of the undecomposed plastic;

Figure 2 is a topography of a plastic surface that begins to oxidize and decompose;

Figure 3 is a surface morphology of a plastic that biodecomposes an oxidized plastic;

Figure 4 shows the plastic surface of the structure that has disintegrated.

detailed description

The preparation method of the present invention will be further described below in conjunction with the examples.

Example 1

Controllable and rapid degradation of plastics, made from the following weight percentages of raw materials: yeast 2%, fast degradation agent 0.1%, volcanic ash 3%, corn starch 5%, calcium carbonate 20%, defoamer 2%, color masterbatch 0.5%, The balance of polyethylene. The fast degradation agent is a d ₃ w degrading agent.

(2) stirring the granules after drying, holding at 120 ° C for 2 hours, and then heating and extruding the blown film to form;

(3) Cooling, crimping the formed film and making a bag.

Example 2

Controllable and rapid degradation of plastics, made from the following weight percentages of raw materials: yeast 1%, fast degradation agent 0.3%, volcanic ash 3%, corn starch 3%, calcium carbonate 30%, defoamer 1%, color masterbatch 0.1%, The balance of polyethylene. The fast degradation agent is a d ₃ w degrading agent.

(2) stirring the particles after drying, holding at 140 ° C for 1 hour, and then heating and extruding blown film forming;

(3) Cooling, crimping the formed film and making a bag.

Example 3

Controllable and rapid degradation of plastics, made from the following weight percentages of raw materials: 3% yeast, 0.5% fast degradation agent, 3% volcanic ash, 8% corn starch, 40% calcium carbonate, 1.5% antifoaming agent, 0.2% color masterbatch The balance of polyethylene. The fast degradation agent is a d ₂ w degrading agent.

(2) stirring the particles after drying, holding at 130 ° C for 1.5 hours, and then heating and extruding the blown film to form;

(3) Cooling, crimping the formed film and making a bag.

Example 4

Controllable and rapid degradation of plastics, made from the following weight percentages of raw materials: 3% yeast, 0.5% fast degradation agent, 3% volcanic ash, 8% corn starch, 40% calcium carbonate, 1.5% antifoaming agent, 0.2% color masterbatch The balance of polypropylene. The fast degradation agent is a d ₂ w degrading agent.

(2) stirring the particles after drying, holding at 120 ° C for 1.5 hours, and then heating and extruding the film to form;

(3) Cooling, crimping the formed film and making a bag.

Claims

A controllable rapid degradation plastic characterized by being made of the following weight percentages of raw materials: yeast 1-5%, rapid degradation agent 0.1-0.5%, pozzolan 3-5%, corn starch 2-10%, calcium carbonate 10-50%, defoamer 1-2%, color masterbatch 0.1-0.5%, balance polyethylene or polypropylene.
A controllable rapid degradation plastic according to claim 1, which is prepared from the following raw materials by weight: yeast 1-3%, rapid degradation agent 0.1-0.5%, volcanic ash 3-5%, corn starch 2-10%, calcium carbonate 10-50%, defoamer 1-2%, color masterbatch 0.1-0.5%, balance polyethylene or polypropylene.
A controllable rapid degradation plastic according to claim 2, which is prepared from the following raw materials by weight: yeast 2%, rapid degradation agent 0.1%, volcanic ash 3%, corn starch 5%, calcium carbonate 20 %, defoamer 2%, color masterbatch 0.5%, balance polyethylene or polypropylene.
A controllable rapid degradation plastic according to claim 1, 2 or 3, wherein the rapid degradation agent is a d2w or d3w degradation agent.
The method for preparing a controllable rapid degradation plastic according to any one of claims 1 to 3, characterized in that the steps are as follows:

(1) mixing and pulverizing each raw material, granulating, and drying the granules under infrared;

(2) After drying, the particles are stirred and heated by blown film forming or extrusion molding or compression molding;

(3) Cooling, crimping the formed film and making a bag.