CN103756146A - Method for preparing foaming material from herbal fibers and plastic wastes - Google Patents

Abstract

The invention provides a method for preparing a foaming material from herbal fibers and plastic wastes and relates to a method for preparing foaming materials. The preparation process comprises the following steps: firstly, diluting a coupling agent by an organic solvent; pre-treating the herbal fibers, which are dried, ground and sieved, for a period of time; then, pre-mixing waste polypropylene and low density polyethylene plastic which are washed and dried, and the pre-treated herbal fibers by a torque rheometer and adding auxiliary agents including a foaming agent and the like; and finally, filling a mould with the pre-mixed raw materials, pressing for molding by a flat plate vulcameter and naturally cooling, thus obtaining the product taken out of the mould. The foaming material obtained by the method has the characteristics of light weight, no toxin, recyclability and the like, and is applicable to the fields of packaging and the like.

Description

Method for preparing foamed material from herbal fiber and plastic waste

technical field

The present invention relates to a method for preparing foamed materials, in particular to a method for preparing foamed materials from herbal fibers and plastic waste.

Background technique

Foamed wood-plastic composites have the advantages of light weight, environmental friendliness and sustainability, and have been widely developed and applied in recent years. In industrial production, chemical products are generally used as raw materials, and continuous mass production can be realized by methods such as injection molding and extrusion.

Due to its refractory degradability, waste plastics have attracted more and more attention to the white pollution of the environment; agricultural waste such as plant stalks and sawdust is generally incinerated, which not only seriously pollutes the environment, but also increases the amount of forest harvesting, which is harmful to the ecology. Environmental protection is extremely unfavorable.

Using herbal fibers to fill waste plastics to prepare composite materials can not only reduce environmental pollution, but also save raw material costs, thereby achieving the purpose of turning waste into treasure. However, due to irregular changes in raw material composition and quantity, injection and extrusion technologies cannot be used for large-scale production. Therefore, it is necessary to design a new method for small-scale production that can flexibly change the formula, appearance, shape and use of the product.

Contents of the invention

The purpose of the present invention is to provide a method for preparing foaming materials by using herbal fibers and plastic wastes. In this method, the coupling agent is firstly diluted with an organic solvent, and then the light-weight, non-toxic foaming material is obtained through pretreatment, mixing and other processes. Materials, and can be recycled, the product is suitable for packaging and other fields.

The purpose of the present invention is achieved through the following technical solutions:

A method for preparing foamed materials from herbal fibers and plastic waste, said method comprising the following processes:

a. Relevant pretreatment of raw materials: impurity removal, drying, grinding and screening of herbal fibers; sorting, cleaning and drying of waste polypropylene and low-density polyethylene plastics; coupling agent, foaming agent, antifungal agent Selection and weighing of additives;

b. Preliminary mixing and pre-reaction of coupling agent and herbal fiber;

c. Use a torque rheometer to add various raw materials in sequence at 180°C and mix them several times for the next step;

d. Use a flat vulcanizing machine for molds to further process and shape the semi-finished products in the previous step, heat and keep them cool, and take the products out of the mold to obtain foamed wood-plastic composite materials.

In the method for preparing foamed materials using herbal fiber and plastic waste, the wood fiber is ground and passed through a 60-mesh sieve, and the underscreen is taken as a reinforcement of the composite material; the weight ratio of wood fiber and waste plastic is 2:8, the additional silane coupling agent is 2.5% of the total raw material mass, the fungicide is 1.5% of the total mass, and the foaming agent is 1.5% of the total mass; first dilute the coupling agent with a diluent and add it to Stir and place in wood fiber for 2 hours, add washed and dried polypropylene and low-density polyethylene waste plastics and stir, add antifungal agent and foaming agent at the same time, knead 5 times at 180°C with a torque rheometer, Then cut it into thin slices for later use; use a flat vulcanizing machine for press molding at 180°C and 10MPa, keep it warm for 20 minutes, and then take out the finished product after natural cooling.

The method for preparing foamed materials by using herbal fibers and plastic wastes includes drying and grinding the wood fibers through a 60-mesh sieve, and taking the under-sieve as reinforcements for preparing composite materials; weighing the wood fibers and high-density polymer The weight ratio of ethylene plastic is 3:7, and the consumption of adding maleic anhydride grafted polypropylene is 1% of total raw material quality, antifungal agent is 1.5% of total mass, and foaming agent is 2% of total amount; The coupling agent is diluted with a diluent, mixed with wood fiber and left for 8 hours, then mixed with cleaned and dried polypropylene and low-density polyethylene waste plastics, and at the same time, antifungal agent and foaming agent are added. Knead at 180°C for 5 times in a variable instrument, then cut into thin slices for later use, pressurize the cut slices at 180°C, 10MPa with a vulcanizer and keep it warm for 20 minutes, then cool naturally and take out the finished product. Advantage and effect of the present invention are:

The method is operated by a two-step method, is simple and convenient, has strong operability, and is suitable for small-scale intensive experiments and production. The product composition and preparation conditions can be changed flexibly, and various experimental conditions can be fully optimized. In addition, the raw materials used, the preparation process and the products are all safe and non-toxic, and domestic wastes are effectively used, which is beneficial to environmental protection and the recycling of materials.

Detailed ways

Below in conjunction with embodiment, the present invention is described in further detail.

Wood-plastic foam composite material is an environmentally friendly packaging material with light weight, sound insulation, heat insulation, odorless and non-toxic. Traditional agricultural waste such as sawdust, straw, and rice husk, which are used as reinforcements in its production raw materials, are often incinerated or discarded in practice, which pollutes the environment and wastes materials. In addition, waste plastics are often discarded at will, aggravating the damage to the environment and increasing the amount of non-renewable resources such as oil extraction. The above production status is not conducive to the implementation of the national sustainable development strategy.

Secondly, in the industrial mass production of composite materials, industrial synthetic products are generally used as raw materials for continuous production through injection molding and extrusion processes. This method consumes a lot of raw materials, and is suitable for large quantities and relatively fixed varieties. However, the above methods cannot be used for the preparation of composite materials from industrial and agricultural waste such as waste plastics and rice husks. The use of expert rheometers and molding techniques can overcome the above problems, which can not only meet the problems of small batch production, but also flexibly change the production varieties and the shape of finished products.

Example 1:

The wood fiber is ground and passed through a 60-mesh sieve, and the under-sieve is taken as a reinforcement of the composite material. The weight ratio of wood fiber and waste plastic is 2:8, the additional silane coupling agent is 2.5% of the total raw material mass, the antifungal agent is 1.5% of the total mass, and the foaming agent is 1.5% of the total mass. Dilute the coupling agent with an appropriate diluent, add it to the wood fiber, stir and place it for 2 hours. Add washed and dried polypropylene and low-density polyethylene waste plastics and stir, add antifungal agent and foaming agent at the same time, knead for 5 times at 180°C with a torque rheometer, and then cut into thin slices of appropriate size for later use. At 180°C and 10MPa, use a flat vulcanizing machine to press and form a suitable mold, keep it warm for 20 minutes, and then take out the finished product after natural cooling.

Example 2:

Dry and grind the wood fiber and pass it through a 60-mesh sieve, and take the under-sieve as the reinforcement for preparing the composite material. Take the weight ratio of wood fiber and high-density polyethylene plastics as 3:7, add the consumption of maleic anhydride grafted polypropylene to be 1% of the total raw material quality, the antifungal agent is 1.5% of the total mass, and the foaming agent is 2% of the total. First, dilute the coupling agent with an appropriate diluent, mix it with wood fiber and leave it for 8 hours, then mix it with cleaned and dried polypropylene and low-density polyethylene waste plastics, and add anti-mold agent and foaming agent at the same time For other additives, knead for 5 times at 180°C in a torque rheometer, and then cut into slices of appropriate size for later use. The cut thin slices are pressurized and molded with a vulcanizer in a suitable mold at 180°C and 10MPa, and kept for 20 minutes, and then the finished product is taken out after natural cooling.

Wood fiber, high-density polyethylene, coupling agent, anti-fungal agent and foaming agent can be selected from common materials.

The above implementation examples have introduced in detail the preparation method of foamed wood-plastic composite materials using waste polypropylene and low-density polyethylene plastics and herbaceous fibers such as wood chips, straw and rice husks. Although it is an example, it is helpful to understand the principle of the present invention and understanding of implementation methods. For those skilled in the art, the core ideas of the present invention will be changed in specific implementations, so the content of this specification should not be construed as limiting the present invention.

Claims (3)

1. utilize Herbaceous Fiber and plastic refuse to prepare the method for foam material, it is characterized in that, described method comprises following process:

A. to the raw material pre-treatment of being correlated with: the removal of impurities of Herbaceous Fiber, dry, grind and screening; The sorting of waste and old polypropylene and LDPE (Low-density polyethylene plastics), cleaning and dry; The choosing and weighing of coupling agent, whipping agent, mould inhibitor auxiliary agent;

B. coupling agent mixes and pre-reaction with the preliminary of Herbaceous Fiber;

C. adopt torque rheometer at 180 ℃, various raw materials to be added successively and repeatedly mix in order to next step operation and use;

D. adopt mould, with vulcanizing press, the work in-process of previous step operation are being carried out to further machine-shaping, cooling after heating and thermal insulation, product is taken out and can obtain foaming wood-plastic matrix material from mould.

2. the method for utilizing Herbaceous Fiber and plastic refuse to prepare foam material according to claim 1, is characterized in that, described by rear 60 mesh sieves excessively of wood fibre grinding, the reinforcement that extracting screen underflow is matrix material; The weight ratio of getting wood fibre and waste or used plastics is 2:8, and additionally adding silane coupling agent is 2.5% of total raw material quality, and mould inhibitor is total mass 1.5%, and whipping agent is total mass 1.5%; First coupling agent is diluted to join in wood fibre with thinner and stir and place 2 hours, add washing dried polypropylene and Low Density Polyethylene waste or used plastics to stir, add mould inhibitor and whipping agent simultaneously, with torque rheometer 180 ℃ mixing 5 times, be cut into afterwards thin slice standby; At 180 ℃, under 10MPa, with vulcanizing press, carry out extrusion forming, be incubated 20 minutes, then after naturally cooling, take out finished product.

3. the method for utilizing Herbaceous Fiber and plastic refuse to prepare foam material according to claim 1, is characterized in that, describedly will be after wood fibre drying and grinding crosses 60 mesh sieves, and extracting screen underflow is as the reinforcement of preparing matrix material; The weight ratio that takes wood fibre and high-density polyethylene plastics is 3:7, and the consumption that adds maleic anhydride inoculated polypropylene is 1% of total raw material quality, and mould inhibitor is total mass 1.5%, and whipping agent is total amount 2%; First after coupling agent being diluted with thinner and wood fibre mix and blend placing 8 hours, the polypropylene good with cleaning-drying and Low Density Polyethylene waste or used plastics mix afterwards, add mould inhibitor and whipping agent simultaneously, in torque rheometer in 180 ℃ mixing 5 times, then be cut into thin slice standby, the thin slice shearing, at 180 ℃, is carried out to extrusion forming and is incubated 20 minutes with vulkameter under 10MPa, after naturally cooling, take out finished product afterwards.