Development of plastic packaging products for the

Development of EPS fired plastic packaging products (Part 2)

4 development increase abroad

at present, developed countries such as Europe, America and Japan are seeking pollution-free new waterproof agents, oil repellents, flame retardants and other auxiliary additives to achieve a variety of functions. Type environmental protection packaging material, is stepping up the research on plant fiber foaming technology, and it is expected that this new packaging material can replace the industrial shockproof lining and liner made of EPS foaming material which is still widely used at present. The methods adopted by foreign plant fiber foaming products mainly focus on the process without adding chemical foaming agent. The raw material is foamed by the action of steam to form granular foamed pulp. The manufacturing process is more difficult than the process of adding chemical foaming agent, but the production and use have no adverse impact on the environment. At present, the following countries have made remarkable achievements in this technology:

(1) the PSP company in Bremen, Germany, uses waste books, newspapers and flour as raw materials to develop the production process of foam paper. Its production process is to cut the recycled old books and newspapers into pieces, and then grind them into fibrous pulp, which is mixed with flour in the ratio of 2:1. The mixed pulp rice is injected into the extruder and pressed into cylindrical particles. During the extrusion process, the raw materials are foamed by water vapor to form foamed paper. Then use foamed paper particles as raw materials to produce packaging products of different shapes according to needs. Compared with foamed plastic, the production process of foamed paper is relatively simple, which can be formed at one time without the process of multiple foaming and cooling. The foaming of the foaming paper does not need chemical additives, but only water vapor. It can be treated like ordinary garbage. Used foam paper can also be recycled and reprocessed, and its production and use will not have a negative impact on the environment. In terms of economic benefits, foam paper is 10% cheaper than foamed plastic in producing the same amount of packaging materials. This kind of foam paper has great application prospects. It can not only be used as packaging materials, but also be developed into insulating materials and building materials

(2) Teijin company of Japan has developed a new environmental friendly foaming material with pulp as raw material. The new foaming material takes natural pulp as raw material and is processed into granular or strip shape, which can be easily molded into various shapes after heating. The foaming rate of the material is high. After expansion, it is as light as the traditional foaming material styrofoam and has the same impact absorption performance. It can be used as an ideal packaging material. At present, the biggest disadvantage of this material is its high cost, which is equivalent to twice that of Baolilong. The company has not yet produced in batch and is trying to reduce the cost

(3) the Japanese Institute of industrial technology has developed a dry pulp foaming technology using waste paper as raw material. This kind of waste paper does not need to be dissolved in water. Compared with the previous wet pulp mold method, the product produced by this technology has better biodegradability and will not cause secondary public hazards. This technology is to crush waste paper to less than 5 mm 'and mix it with starch paste to make particles with a diameter of 1 ~ 3 mm. Blow the particles into the open metal mold, and then close the metal mold for pressure heating. The moisture contained in the paste is discharged from the vent during the heating process, which can be made into packaging products with precision and wall thickness corresponding to the metal mold. When making foaming packaging materials, small particles of waste paper and starch paste can be foamed in advance, and the foamed body is coated with starch paste and blown into the metal mold, or small particles can be added into the foaming material to make it foamed in the metal mold. Because this technology does not need a lot of water, it does not need to be equipped with drying lines and wastewater treatment equipment like wet pulp mold products

5 domestic research status

several colleges and units in China are carrying out research and development of this technology, and have achieved phased results. It can be considered that it is possible for this technology to go out of the laboratory. The process method of plant fiber foaming products developed and studied in China mainly focuses on adding chemical foaming agent, that is, using foaming agent to produce foaming. The raw material is foaming through the action of chemical foaming agent to form granular foaming pulp. The process of using foaming agent is simpler than that without foaming agent, but for example, the carbon dioxide absorption mask and heat-resistant jacket made of pet aerogel can be placed in 1 with the fire extinguisher of high-rise buildings, and can also be used for other elastic components and small-scale mechanical property experiments. The foaming method and products of this kind of plant fiber may cause some adverse effects on the environment in the production process and post-use treatment, Therefore, this technology needs to be improved. At present, the following units have made some progress in the development and research of this technology:

(1) Guangdong University of technology has studied the foaming technology of pulp vacuum formed products, and proposed the method of low-temperature foaming of paper products (generally not more than 150 ℃), which can be carried out outside the mold cavity or during the drying process of products. The University also conducted a preliminary study on the performance

and structural characteristics of the foamed paper holder. The research shows that the tensile breaking strength of the products decreases with the increase of the amount of foaming agent, and when it reaches a critical value of

, the breaking strength begins to decline sharply. When the foaming degree is not too large, the maximum height of drop increases with the increase of foaming degree, but when the foaming degree reaches a critical value, the maximum height of drop begins to decrease with the increase of foaming degree

(2) Dalian Institute of light industry has carried out research on the technology of dry pulp mold casting to prepare light packaging materials. The main processes are: crushing of waste paper, preparation of starch paste, expansion of small particles and molding. Among them, the preparation of starch paste and the expansion of small particles are the key technologies in the whole production process. Compared with the wet formed pulp molding packaging materials, the dry molding process greatly reduces the amount of water needed to evaporate in the production process, and greatly reduces the energy consumption in the production process

(3) Nantong Institute of technology studied the use of natural plant fiber materials, using inorganic foaming agents (mainly nahcos, NH. HCO), glue.

adhesives and other additives, through integral pouring, one-step foaming molding. This method has high requirements for molds. The anti-seismic cushioning performance, compressive strength, cell structure, foaming multiple and density of the product have been preliminarily studied (4) the double foaming plant fiber material developed by Wuhan Far East green world company can be used in household appliance manufacturing enterprises to replace the foam plastic package. E material is produced by using modified starch and high fiber filler as raw materials, with the action of foaming agent, through low-temperature foaming granulation and high-temperature foaming technology. It has the characteristics of dampproof, earthquake resistance, compression resistance, light strength and low price. The degradation rate of the material can reach 78.4%, which is a new environmental protection packaging material. This material is plastic

packaging material. What we share today is an excellent substitute for the operating procedures of pendulum impact testing machine. Combined with plastic foam packaging materials, it can completely disappear after 24 hours in the open air, which is more than 15% higher than the national degradation time

6 existing problems and Countermeasures

(1) focus on developing batch experiments that have no impact on the environment: plant fiber foaming technology for samples with the same parameters

in China, the existing research and development methods of plant fiber foaming packaging products are mainly carried out by adding chemical foaming agents. Foaming agent will have an adverse impact on the environment, so we should vigorously develop and research the use of water vapor to achieve plant fiber

(2) strengthen the development of industrial production technology and equipment for plant fiber foaming products

at present, whether at home or abroad, the research on plant fiber foaming products is basically still in the laboratory stage, and has not reached the requirements of industrialized large-scale continuous production. In order to achieve this goal, We should strengthen the research in the formulation of products, the selection of process parameters, the development of special equipment, the design of special molds and so on, especially in the realization of meeting the requirements of continuous and automatic production

(3) conduct a comprehensive and systematic study on the characteristics of plant fiber foaming packaging products

at present, the research on the performance characteristics of plant fiber foaming packaging products mainly focuses on single piece and experimental aspects, while the performance parameters of multiple pieces or practical applications have not been verified. Therefore, in this regard, we should strengthen the research to obtain the performance parameters of plant fiber foaming packaging products under various actual use conditions, In order to carry out targeted improvement and improve the comprehensive use performance of plant fiber foaming packaging products