The use of waste plastics and modified - injection molding machine

Date：2016-07-12 14:10:11

As we all know, injection molding machine industry, including the plastics processing industry and synthetic resins, processing aids and other raw materials, injection molding machines and die processing machinery manufacturing and other industries, have already become an important part of our national economy. 20 years of reform and opening up, China's injection molding machine product has maintained a sustained and rapid development, the annual production has more than 20 million tons, ranking second in the world, to become a truly great power injection molding machine. Injection molding machine industry itself is not the "white pollution" the source, must be emphasized that the process of recovering from the production and consumption process to use after value may be reused three terms, injection molding machine industry itself is a green industry, as long as we recycle and do a good job recycling, injection molding machine industry development and protection of the natural environment will be able to live in harmony, to create a win-win situation. In the new century, the injection molding machine industry will continue to become a thriving, hidden opportunities sunrise industry.

Plastic injection molding machine as a new polymer material has been well known, accepted, injection molding machines plastic materials and products have been widely used in various fields of society and people's lives, has become an indispensable part of life. But for various reasons, post-consumer plastics in the environment caused direct or indirect damage caused by the growing concerns of the community, to eliminate "white pollution"

Incessantly. Injection molding machine industry to sustained and rapid development, we must face up to some of the negative impact brought about by the injection molding machine industry in the development process, and the recycling of waste plastics and make use of scientific and rational, is an important area of ​​the injection molding machine industry should not be underestimated, it not just to deal with the community of life, and to achieve "recycling economy" to maximize the use of limited resources on Earth to better serve humanity. Of course, as with waste plastic recycling-based industry, companies first need to face is the normal operation of the enterprise, you must obtain profits and benefits. Inconceivable that the socialist market economy into the enterprise solely for the protection of the environment and renewable resources exist without taking into account their own interests, this pure social welfare-oriented enterprises unless special care the government is unlikely to survive. Over the past few decades, there have been in the plastics industry for recycling of waste plastics industry companies many government departments in charge of investment in the 1980s was also the introduction of foreign advanced cleaning, grinding, granulation equipment, but to today, little has been stored, while the real existence, but also thriving touches countless large and small private enterprises or individual households, the existence and healthy development of these enterprises will undoubtedly give us 3:00 Significance: many waste plastics, waste plastic recycling do use paper promising; what to do with waste plastic, how to have the lowest cost to make use of the product is the key to recycling enterprise survival and development; now waste plastic recycling business demand for technology is very urgent, if we recycle technology, better equipped, stronger, higher, then the waste plastic will no longer be a social package cloth for carrying baby, but will become a very lucrative valuable resources and wealth.

1 policies of waste plastics processing plastic products with an annual output of more than 4,000 US tons of waste plastic generated hundreds of tons per year. The main way past consumptive waste plastic is landfilled, while declining land for landfill, landfill costs and ecological impact of the landfill on the environment and other issues gradually shifted burning heat extraction. Using incineration of waste plastic has reached about 20% of total waste. The United States had hopes of degradable plastics, plastic material degradation hopes to achieve the sound and mitigate waste plastic processing pressure in their own environment.

So far due to degradation art does not achieve the desired results and the full utilization of resources voice rising, the proportion of all plastics biodegradable plastic products is very small (about 3%), while the waste plastic recycling is still subject to certain attention. But American power status, its recycling focus only on the production process of recycling scrap and substandard goods, for those who still have a certain value in use, but the need for cumbersome process, especially to spend a lot of human waste plastic, the US is always trying to be transferred from the local community to relieve the pressure in their own treatment.

Europe is not exactly the same situation, the proportion of incineration process has gradually declined, replaced gradually improve the urban and residential waste collection, to be dealt with separately approach. I was in Paris to visit a nearby residential community of 100,000 people, the government commissioned a local company specialized waste collection and disposal, and has a whole community can eat garbage treatment plants, each about two big fermentation tanks 60 meters, a lot of waste plastic film bag is pulverized to a size of a fingernail flake or short strips, mixed in fermented slag, reportedly transported to a nearby vineyard. In Italy we visited a nearby Milan waste plastic recycling plants, filled with a variety of outside plant waste plastic film or bags, according to the boss said it was government money the sale of transport, sent here to free them in use. Of course, as a result of the overall balance of the pros and cons, other treatment methods such as pyrolysis in Europe, incineration, landfill, also occupy a certain position.

Japan's land area is small, there is no land for the landfill, and the population density, the total amount of plastic waste is also large, the government and industry associations have set up a special emphasis on the recycling of plastic waste, but is currently still dominated incineration. In 1994 the total output of 13 million tons of plastic Japan, waste plastic of about 400 million tons, which accounted for 25.5% landfill disposal, incineration (56%), extracted thermal power accounted for 18.5%, is evident. Incineration impact of environmental pollution on Japan because Japan is a small island main things Homeland narrow, two sea, burning smoke can spread rapidly. This is also the Japanese incineration dominate a situation. China has been a large number of export calcium carbonate containing up to 30% of the garbage bags to Japan the key is calcium carbonate contained in garbage bags in favor of combustion in incinerators.

China's national conditions with the United States, Europe, Japan is different from the average of our population resources are not well-off, the current annual oil imports have accounted for the total consumption of 1/3, while the vast majority of our population concentrated in eastern and central, arable land especially around the town is very valuable, it is impossible to valuable land indefinitely used as landfill. At the same time on our situation and the level of equipment geography technology, both the pyrolysis or incineration extraction on the environment will be more serious pollution of heat, it is not worth the candle. People for degradable plastics have great hope in it as to eradicate the "white pollution" of magic, but the ruthless reality shows, biodegradable plastic products and application technology still has significant limitations, the market has not yet been generally accepted, especially with regard to "single-use plastic products after disposal also a very high re-use value, all made of biodegradable is not a great waste of resources," the debate, there has been in the business community and the academic community. So clearly stated, "to recovery and recycling mainly to landfill, pyrolysis, burning, biodegradable and other ways to supplement" should be the most realistic treatment of waste plastics, the most scientific, the most dynamic and promising According to our country principles and policies.

Our industrious and thrifty world-famous in the era of scarce resources, are very natural treasure for any substance, the so-called new three-year old for three years sewing for another three years from the date of this glorious tradition plastics industry was born of deeply rooted among the industry. Recycled plastic products as early as the 1960s, repair old enterprises and various plastic waste on our lives very close.

It is most familiar with plastic soles, especially on dividends bottom shoes, black and white, white people know better, because it is made of new material, and the red, the black matrix is ​​made of recycled materials. In 1975 the former Ministry of Light Industry has held the "National Waste plastics recycling experience exchange", Shanghai and other plastics industry department also specially prepared brochures and books. In the 1980s with the progress of reform and opening up, a large number of advanced technology, equipment introduction, our country has been in the framework of a planned economy, according to the national distribution of each region, were the introduction of six sets of plastic waste in Japan or Europe, cleaning, grinding, granulation equipment, material recycling industry has also recovered to something deep processing, the introduction of similar devices, such as in Beijing to set. At that time engaged in recycling, cleaning, granulation or direct molded products business there are hundreds. In 1993 the former China Plastics Processing Industry Association held plastic waste Recycling of exchange, a total of more than 20 provinces and cities more than 300 people attended the meeting in Taiyuan, Shanxi. At the meeting on China Injection Molding Machine Industry Association of Professional Committee of plastic waste recycling was set up, marking the industry department in charge of waste plastics processing attention.

With the accelerated pace of reform and opening up of China, the synthetic resin material injection molding machine processing required not only in the country to obtain, and the massive influx of foreign raw materials abroad, as the significance of waste plastics recycling plastic materials using injection molding machines rapidly become smaller, value and status decreased rapidly, but also led under the planned economic system to the waste plastics recycling as the main business of many companies are not profitable collapse or converting to a new raw material-based products. But we also see that, in accordance with the rules of market economy, a large number of new waste plastic processing enterprises have emerged in many cities spontaneously formed a sizable waste plastics distribution market, new recycling, recycling technology and equipment has also been It emerged, but also close to the situation, close to the market, close to the downstream users, more vitality. Years of practice has proved that the recycling of waste plastics recycling and the pace never stopped, waste plastic recycling aspect of scale, technology and equipment and the applications of recycled products is not less than abroad, some areas do better than even better abroad, and even reached the international advanced level.

2 waste plastics use, modification technology status and problems of today's waste plastic recycling has been out of the narrow concept of pure thrift, which has environmental protection and recycling of resources is caused by the sustainable development of the national economy and other strategic measures together, we should fully understand the importance of working in this field from such a height and in a timely manner to solve the problems faced.

From the current domestic situation, the plastic waste can be attributed to the following four categories: Category 1: has entered a virtuous circle, it is possible to achieve better efficiency, recycled products have a clear purpose, such as: a molded plastic woven agricultural plastic greenhouses bags, woven cloth, plastic packaging with bottles, hollow barrel, cosmetic bottles of pure d daily necessities plastic parts, shell, etc. e. wire, cable plastic sheath above plastics recovery and recycling the main problem is the low level of technology and equipment , in the regeneration process, the low value of the actual material properties are damaged to varying degrees, after regeneration. A so-called feed back, two back and other materials, the value per tonne based on the level of recovery technology can be a difference of thousands more.

Category 2: the production process or scrap imported from abroad, can be processed into recycled materials, with better performance and application market, but also to gain market recognition, benefits are good. The main problem is the need to identify the type of plastic has a higher knowledge and experience, but also easily lead to serious incidents of plastic waste imports. Such waste plastic scrap such as VCD discs, beverage bottles, substandard film, sanitary napkins and diapers scrap, as well as home appliances, computer casings, parts.

Category 3: have appeared in large numbers but limited economic interest, failed to enter the market and business vision, such as EPS foam, foam disposable tableware, all kinds of vest bags, shopping bags, single or composite packaging film and the like.

These products discarded after use, falling into the street, on both sides of roads, rivers and lakes become condemned the "white pollution", should proceed to a comprehensive solution from all aspects of administrative, technical, economic levers, the quality of people like.

Category 4: With the use of plastic injection molding machines expired or available as accessories, speed up the upgrading of its main articles, some plastic waste will have emerged, many of these materials by the modification, or composite of different materials, such as televisions, home appliances, computers, cars used on various parts, and some are already crosslinked or surface has been coated or composite thermosetting plastic layer, it is difficult with the approach commonly used, such as cleaning, grinding, melt granulation method of recycling. In this regard we have no better way, also failed to make full technical preparations in this regard.

3 Some waste plastics recovery and recycling technology of waste plastics recovery and recycling technology is directly related to some kind of plastic waste can not be recycled, regenerated or without use, enterprise investment project in addition to the presence or absence after social economic issues. With the advent of a technology and gradually improve, it is possible to radically change the fate of all sectors of society and a certain kind of waste plastics face it understanding.

3.1 WPC plastic wood-plastic composite is simply understood composite wood and plastic, we refer here to flour or rice husk, straw and other natural plant fiber material has been crushed to a certain fineness and after plastic composite, also plastic fiber can be called day.

In the days of plastic fiber, wood flour or rice husk, straw powder accounted for half and can use waste plastics, and products made from composite can replace natural timber cargo transport indispensable pallets or other packaging, construction, and other aspects of daily use. Days fiber material properties of plastic between the synthetic resin and natural wood, see Table 1. Days fiber as raw material of plastic trays fully meet the relevant national standards (GB / T4996-1996 and GB / T4995-1996 universal intermodal flat pallets test methods, performance requirements), while avoiding the wooden pallets must be fumigated export requirements, simplify the export procedures and customs inspection procedures.

Of course, days defibrillators plastic processing technology is more complex, and the difficulties in the main process as follows: Days fiber plastics common plastics and performance comparison with the performance of the project of common plastics natural wood ordinary plastic fiber tensile strength of timber days Medium Medium high flexural modulus low medium high high high impact strength, rigidity and load carrying capacity medium medium high high water absorption featuring the high acid and alkali resistance to aging low good poor good recyclability easy hard easy low high low cost products days fiber material crushing and pre-processing (including drying and surface treatment) is first necessary day-fiber material crushed to a certain degree of fineness, generally require tens head.

Day of natural dry state fiber filler moisture content of 5% or more, and some can reach more than 15%, so as a plastic filler must be dried, the drying temperature should not exceed 200 * C. Chemistry Day fiber mainly composed of cellulose such polyols in the molecular structure and polarity point of view, with the usual polyethylene, polypropylene and other plastics have considerable variation, and must therefore be treated before the composite surface. Since the days of the porous fiber filler, often unfit for use mineral filler surface-treated with a coupling agent, according to research Beijing University of Chemical Technology, when the substrate is a polypropylene plastic, the use of MAH-PP on the day of fiber is coated fillers the most suitable, when the base plastic is high density polyethylene, the treating agent is an ethylene - acrylic acid copolymer (EAA) is the most suitable.

Processing Research indicates days defibrillators plastic wood flour-filled polypropylene system belongs to pseudoplastic fluid with the increase of shear rate, the apparent viscosity of the material decreased significantly. While the other is characterized by wood-plastic composites are very sensitive to processing temperature, which means that when the extrusion small temperature fluctuations, the viscosity of the material can make great changes, thus affecting the stability of the extruded material. The other is to consider the thermal stability of the fiber filler day, decomposition and charring occurs when the temperature is high. Experimental results show that appropriate to reduce the extruder temperature, increase head pressure, reduce the screw speed can be effective in improving the extrusion processability days defibrillators plastics.

Studies have shown that processing equipment, a single screw extruder day processing fiber composite plastic production profile has a cross-sectional shape, but must be vented extruders, and screw configuration on the day of fiber filler in the matrix of plastic dispersion significantly affected. Beijing University of Chemical findings that the use of a screw pin mixed material mixing effect is better than ordinary screw.

From practical experience home and abroad, before a single screw extruder, extrusion molding, the surface has been treated Days fiber filler and matrix plastic to go through the same parallel twin-screw extruder mixing granulator is essential . Accordingly days defibrillators plastic molding process requires quite advanced and complete set of devices and equipment, or the mere simple process and general single screw extruder is difficult to make day-fiber composite plastic material properties meet expectations.

3.2 Collection and recycling of polystyrene foam plastic injection molding machine using well known, recently a hot topic during the siege of disposable lunch boxes made of polystyrene foam. For a certain specific plastics, national governments, the media, the community give such attention and concern in the history of industrial development in the injection molding machine is no precedent. In fact, the annual output of plastic foam lunch boxes and other disposable cutlery is only about 50,000 tons, accounting for 0.25% of the country's total output of plastic products, even if all the cut and no concern presses the overall industrial development. But we should see the importance of the injection molding machine industry and environmental protection from the joint development on this issue. Environmental pollution caused by polystyrene foam tableware just stay in people's vision, yet the soil, air, water, bring direct harm, if we are careful study and mass production of plastic products almost everywhere, both in production during or after use are likely to harm, directly or potentially on the environment of human existence. Such as processing aids are a variety of chemicals, some of the health hazards of operating workers, distributing some harm to the atmosphere more people, even the ozone layer are destroyed; and if processed into windows and doors of PVC profiles applied to buildings, and to become national leaders down to ordinary common people are to be recognized as to focus on the promotion of plastic products in the new century, not knowing when the building is on fire, make these plastic materials to produce gas suffocation deaths the danger is much greater than wood, steel and cement, these materials at high temperatures to produce toxic smoke off the time to reach a certain concentration to cause death, that is, to give people time to escape a fire only a few seconds to a few minutes to calculate the occurrence . If there is a direct or potential harm, whether this material, the product must be banning the production and sale of it, and if so, technological progress brought civilization is running out.

We are white pollution problem to be properly treated, scientific, positive attitude to take appropriate measures, not encountered the problem of a ban. We engage entrepreneurs and scientists produce plastic materials and products should also seriously consider why one kind of great convenience to people's lives, safe and sanitary, cheap and easy to use foam products will embark on the road to ruin it, the reason is because we fall to such a fate only busy producing and making money, not to deal with the development of production and environmental protection relationship between the two. If we used foam plastic tableware are to be recovered and recycled, if they do not see on the street, both sides of the roads, rivers and lakes, who will be issuing the order to cut-off disable it, why beer bottles, cans is caused by plastic beverage bottles can be recycled it seriously, the most fundamental reason is that the law of value at work.

So can someone go to recovery, the real treasure as waste, is the primary problem. Beijing Experience shows that when the price recovery snack reached 240 yuan, some people do it voluntarily, evidenced by the lever of economic recovery is not difficult. But another problem is that the recovery of any use to the lunch boxes, is able to create new value is also related to recycling and reuse can stick to it, can promote in a wider range.

Today newspaper reported on foam lunch boxes still continue unimpeded, admitted by the so-called eco-friendly tableware do. Leaving aside the various alternatives we estimate it really "green", but to face the reality. Foam polystyrene foam lunch boxes is only a small category of products, all kinds of polystyrene foam products are currently more than 60 million tons, with a shock-absorbing packaging materials discarded after more than half, and this part of the article is the use of other types of materials can not. We focus on environmental protection and joint development of the injection molding machine industry, it must include disposable foam plastic dinnerware, including all polystyrene foam recycling and reuse issues to be scientific and reasonable solution.

The reason why the foam is difficult to recycle, mainly light bulky, high transport costs. Which we advocate first-place foaming, then the volume of polystyrene foam using transportation that is a non-solvent type heat medium method collected in a very short period of time (tens of seconds to minutes) is reduced to the original 1 / 30, to return to a density 0.9g / cm3 or more. Foam recycling reuse is another problem many impurities, especially disposable lunch boxes, leftovers, leftovers, toothpicks and oil, etc., like other difficult as recycled plastics and new materials blended use of them must be found impurities less sensitive uses, and use recycled materials to make a lot of money to have the added value of products, in order to bear the cost of recycling and regeneration. Through various comparison, we believe that the use of such anti-foaming polystyrene foam recycling technology and re-processed into polystyrene foam sheet and used for the production is feasible for such a cold plate or large plant room roof, pipe insulation and other insulation, and insulation materials available its director, to avoid it short, compared with the new expandable polystyrene (EPS) pellets can be significant savings in raw material costs. At home and abroad and the recovery of polystyrene foam recycling technology very seriously, a lot of reports, the technical route and use no more than: a) melt granulation, b) pyrolysis to extract styrene monomer, c) organic solvent for dissolving the binder do, d) direct crushing and mixing cement and other building materials to make lightweight and other four categories. The technology has not been able to promote its large main issues are: (1) regeneration of low value-added products; (2) the performance of recycled materials has been severely damaged; (3) the recycling process is easy to produce secondary pollution.

Non-solvent type heat medium defoaming technology we invented not only will not produce new pollution, physical and mechanical properties of materials and the recovery will not suffer substantially, its defoaming regeneration cost is very low, is the most scientific, technical best economic recovery and utilization. The outcome in 1998 passed technical appraisal chaired by China Light Industry Association, experts from the competent authorities, universities and research institutes agreed that the outcome of the Styrofoam recycling and reuse technology has reached the international advanced level. We want visionary entrepreneurs to work with us this industrialization of research results, polystyrene foam is no longer a nuisance, to solve the "Paper Debate" for the plastics industry sustained and healthy development to contribute!

A few years ago the use of 3.3 PP / LLDPE composite scrap plastic materials Co., Ltd. of Zhuhai West Coast group of plastic scrap imports from abroad, the analysis is that polypropylene (PP) and linear low density non-woven polyethylene (LLDPE) film composite sheet material together, in an artificial way to separate the two is almost impossible, but in the extrusion granulation process due to the difference between the processing temperature and the melt viscosity difference between the two is difficult to mix evenly. Such scrap is very clean, free of impurities, mostly white and sky blue color, and physical and mechanical properties of the material itself should have not been any damage. We believe that the key to re-use this material to find the best use is not isolated and mixed-use. After research and experimentation we consider it as a carrier resin filler most suitable, because (1) filled masterbatch production, annual output of hundreds of tons required as polyethylene, polypropylene and other polyolefin resins as carriers tree month aimed at least 5 tons, the market capacity is great, (2) the PP and LLDPE mix is ​​a lot of filler plant normal production methods, many companies it is the polypropylene pellets and polyethylene pellets were mixed together used as a starting material, (3) a composite sheet material simply processed in pellet form acceptable for sale to the user. The current group of pellets sells for 4,200 yuan / ton. Than the new polypropylene or polyethylene resin is 20% cheaper to 30%, with each one ton of this recycled material can be filled masterbatch producers to bring the benefits of nearly 2,000 yuan, so welcomed by users.

The work we do is based on the mechanical properties of such composites and material composition, processing flow for determining performance ratio of filler and the appropriate adjustments when processing conditions.

The success of this technique is that we're looking for the best use of specific methods and uses waste plastic, not only can the recovered scrap is well spent, but also bring significant benefits to users. This recycling of waste plastics technology undoubtedly has a strong vitality.

4 of waste plastic recycling waste and modification Outlook Despite the recovery and use of plastics, whether or from the perspective of environmental protection point of view, are of great significance from the perspective of renewable resources, but we still can not guarantee that all waste plastic can be recovered and reused. Recycling costs on the one hand too high so that enterprises can not afford to play only active in social tasks, on the other hand emerging new materials, new design manufacture these materials tend to consider how to meet the requirements, neglected after use can be recycled the problem, our recycling technology progress and sometimes can not keep pace with the development of this new material. Such as paper-plastic, aluminum-plastic composite materials have good adaptability packaging (such as soft drinks) and freshness barrier (aluminum foil can effectively block the air), but only drinking the beverage or food to eat will put the box contents bag dropped, although the material properties are not compromised, but it is difficult to recycle and reuse. Another example is the anti-aging material in order to make the environment in order to improve the strength of the material, we are now developing cross-linked material, such as communications, power cable sheathing material, cross-linked polyethylene water pipe, foam and the like. After these crosslinked materials, whether chemical crosslinking or radiation crosslinking, are difficult to recycle and reuse plus. We should require the design and production of a material or article must be considered recyclable after its use in order to minimize harm to the environment level, but obviously this is only the direction of the efforts in the foreseeable in quite a long time it is difficult to fully achieve.

Existing waste plastic, proper and reasonable treatment, it can be used, there is considerable value in use portions separated and with scientific, technical and economic aspects are two possible ways to make good use of the waste is placed in plastic recycling an important task before use front. Progress in this area of ​​technology is also very significant, you can spend some immediately, some may still need further improvement. Some aspects still need to work on our research, invent, create.

4.1 Identification Identification and separation of waste plastic is not only necessary but also considerable difficulties. Experienced people can look, feel, smell, density and other methods to distinguish different plastic open. There are common methods by flames, smoke and odors when burned to be judged, if necessary, can be used infrared spectroscopy, nuclear magnetic resonance to determine the molecular structure of the material. But because now a lot of material through filling, blend, made of composite and other methods, determine the composition of its great difficulties. So far we still lack the system introduced in this regard and books.

For some not easy to distinguish the appearance of the material may be unique equipment and methods. Transparent PVC bottles such as PET bottles and the same transparent, France on a dedicated instrument with infrared radiation, operators wear special glasses to be observed under infrared irradiation at different brightness of two different materials rendered bottle, thereby identification can be clear.

Abroad for different types of plastic injection molding machine with a composite plastic waste tend to use gravity, centrifugation and separation of electromagnetic fields and other methods to separate. Since these methods, although the principle of science, investment, high cost, in our country is still difficult to promote.

Whether it is usually pulverized pyrolysis, melt granulation or direct composite regeneration, waste plastics need to be crushed. Since the waste plastic material involved itself modulus, strength, elongation, toughness and other properties vary widely, as well as plastic material properties at room temperature and low temperature performance was very different, so crushing equipment and operating conditions is vastly different. We are now a common mechanism mill divided by shear, impact, vortex, turbine and other types of waste plastics for the majority has the right equipment and appropriate operating conditions.

Progress crushing equipment focused on how the waste plastic has a certain toughness to tens of crushing fineness purposes, for which there are low temperature shredders, vortex or turbine mill and particles grinder, etc. appear. We can choose according to the nature of the material to be crushed and pulverized target appropriate grinding equipment, but we can always request still at room temperature, energy consumption will be relatively small crushed waste plastic to the desired fineness, and hope durable equipment, and clean-up operations should be easy.

Modified in the case of the two plastics composite and not readily separated, of course, is not the best use to be separated can be used, as previously described PP / LLDPE composite membranes can be directly used as filler carrier resin. But if the two plastics polymer structure from the point of view are mutually exclusive, such as PVC and PE, PP and PA, etc., can not be separated from each other in the case of a third substance may be added, or a compatible agent, or and two kinds of plastics have another plastic better compatibility. E.g., chlorinated polyethylene (CPE) can be used a mixture of polyethylene (HDPE) and polyvinyl chloride, ABS may be used a mixture of PE, PP, and polystyrene, a styrene-butadiene block grafted maleic anhydride copolymer, maleic anhydride grafted polyethylene compatible agent may be used in a mixture of HDPE and PET, etc., this method is called modified blend Capacity modification.

Some waste plastics reasons color, impurities, etc. are no longer suitable for the production of film and high surface quality of plastic products, but can be added mineral powder, wood flour and other weaknesses, there can also be made use of material or article is just an example. made of fiber composite plastics days previously described, as well as pots, buckets, tools and so on. This technique is called Filled. The key is whether the surface treatment of the filler properly.

The waste plastic by catalytic degradation or chemical substances added to change its molecular structure, can be obtained valuable products. Such as waste plastic car often covered with paint, metal and other materials, and many have been cross-linked, to be treated with the conventional recycling method is not suitable, then recovered by degrading the monomers and low molecular weight alkanes. Another example is a polyester (PET) waste through thickening, high molecular weight resins can be re-used for spinning or doing pipes, hollow containers. This relies on chemical reaction waste plastics to chemical modification called regeneration.

In addition to recycling waste plastics used in plastics raw materials or the corresponding chemical products by pyrolysis, but also the direction of development should be classified as other non-polymer material and is directly in combination. Ministry of Metallurgical Construction Research Institute of years of research for the waste polystyrene foam wall insulation, they are made of cement polystyrene board polystyrene foam particles, cement, foaming agent by mixing a casting molding new types of insulation sheet, light weight, low thermal conductivity (good insulation) advantages, there are certain mechanical properties, it can also be made of fiber reinforced if necessary. They make cement polystyrene board products used so far 500,000 square meters in terms of energy-saving building insulation facades.

There is also the foreign waste plastic plate or telephone Kartchner into fibers, and then filled into cement concrete, significantly improve the bending strength of concrete and the like.

4.4 Supercritical water degradable waste plastics technology 3 * Q critical pressure of 2205MPa. When the temperature and pressure exceeding the critical temperature and critical pressure, the water in the supercritical state, at this time is called supercritical water under normal water has a 7 performance of the organic solvent that can dissolve organic, inorganic without dissolving, and this time the supercritical water can be completely miscible with air, nitrogen, oxygen and carbon dioxide gas.

Waste plastics were degraded with supercritical water or developed in recent years in Japan, the United States have conducted extensive research. Japanese Patent Useful supercritical water of waste plastic (PP, PE, PS, etc.) are described degradation recovered, the reaction temperature is 400 ° C ~ 600 * C, the reaction pressure was 25MPa reaction time is 10 minutes or less, and get more than 90% oil ratio.

Waste plastics with supercritical water degradation of its advantages are obvious: do a water and low media cost; b avoid charring phenomenon pyrolysis; c reaction is carried out in a closed system, not new to the environment.

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