China is a big country in the production and consumption of international packaging. The proportion of plastic packaging and paper bag machine packaging in the total output value of the packaging industry has exceeded 30%. It has become a new force in the packaging industry, in food, beverages, daily necessities, and industrial and agricultural production. Plays an irreplaceable effect. In recent years, packaging products and packaging materials for the plastic packaging and paper bag machine packaging professions have increased steadily, and new packaging materials, new skills, new skills, and new products have continued to emerge.
        Packaging is one of the most important application areas of plastic materials, especially for thermoplastic materials. The demand and development of the packaging industry directly change or guide the development direction of plastic materials production and processing skills. Generally speaking, plastic packaging and paper bag machine packaging materials and finished products are facing infinite pressure in three aspects: First, advance the functions of finished products, such as increasing the transparency, heat resistance, mechanical strength and barrier of materials and finished products. Sex, etc.; the second is the pressure from environmental protection; the third is the pressure to reduce costs. The result of the three aspects restricting each other and mutual effect is that, except for a single occasion, as long as the materials and finished products that can reach the concession in these three aspects have the largest market space. However, the demand will always drive the advancement of skills, and advancement of skills continues to invent the wonders of high quality and low price. Many materials that were previously quoted at high prices have now fallen on a large scale due to large-scale production.
        1. Finished packaging is the most important application category
        At present, the plastic products produced in my country are mainly plastic films (including agricultural films), plastic filaments and woven products, plastic pipes and daily-use plastic products.
        If distinguished by application, packaging products are one of the most important plastic applications. It is estimated that by 2005, my country's demand for plastic packaging and paper bag machine packaging products will reach 5.5 million tons, accounting for 22.0% of the total demand.
        From the perspective of the primary plastic varieties, in the field of plastic packaging and paper bag machine packaging, the consumption of high-density polyethylene film will continue to increase steadily; the application of hollow products will develop in the direction of multiple varieties, diversification and specialization; multi-layer co-extrusion The output of plastic hoses, plastic bottles for medicines, and various hollow containers will increase significantly. The proportion of polypropylene spent on injection molded products will continue to increase. The polypropylene used in film products will also increase rapidly, but in the application of woven products, the proportion of polypropylene spending will be significantly reduced. Polyvinyl chloride products will mainly be concentrated in the field of construction, and the use of packaging in the field will be further reduced; finished film products will be more replaced by polyethylene film. Due to the "white pollution" problem of polystyrene fast food lunch boxes and other foam materials, the amount of polystyrene foam products in packaging will gradually shrink.
        2. Development of commonly used plastic packaging and paper bag machine packaging materials
        PE, PP and PET are the three most commonly used materials for plastic packaging and paper bag machine packaging. Secondly, materials such as nylon, PC, and PVDC are also used in packaging.
        PE: Non-polar and polar ethylene copolymers and metallocene ethylene are currently the two hottest topics in European and American countries.
        Ethylene copolymers can advance the stretching and co-extrusion functions of the plastic film, and advance the transparency, enhance stability, improve molecular weight distribution and extrusion rheological functions. VLDPE (ultra-low-density polyethylene) is replacing LLDPE, PP, EVA, and PVC in the extrusion, injection, and blow molding technologies, occupying the flexible packaging market for medicine and cosmetics, and will impact the food packaging category. Linear ethylene copolymer and ethylene-vinyl acetate copolymer are used to produce PA bags, which are also used in food packaging such as ice cream and milk fat.
        Metallocene polyolefin is a polymer prepared by olefin polymerization reaction using metallocene coordination compound as a catalyst. Metallocene polyethylene has many advantages, such as good gloss, high melt strength and film stability. It is suitable for food packaging and has been paid attention to by the industry. It is widely believed that metallocene plastics will directly impact the plastic market such as PP, MDPE, LLDPE, and elastomers.
        At present, the demand for PE in the international market is 40 million tons, and it is estimated that it will increase to 50 million tons by 2005. Most of the increase is metallocene polyethylene.
        PP: The performance of PP is very lively. New PP trademarks and modified PP materials are emerging one after another. Since many modified PP have the characteristics of engineering plastics, they have now replaced engineering plastics in an appropriate range.
        Tongming PP is a fast-developing product, and its application in medical products, medical packaging products, and cosmetic packaging is increasing. Because BOPP bottles can withstand high temperatures above 100°C, they have been widely used in large infusion and functional beverage packaging. BOPP film is the fastest growing variety of plastic film. Multi-layer co-extruded BOPP film is the current trend.
        PET: PET is also one of the most active plastic packaging and paper bag machine packaging materials.
        PET bottles are the primary beverage packaging method. However, due to the poor high temperature resistance of PET, PEN, which has a molecular structure similar to PET, has always been valued by the industry. In addition to good heat resistance, PEN has better barrier properties than PET, especially gas barrier properties and UV protection. In the near future, PEN will surely enter the food packaging category, causing another packaging innovation after PET.
        PC: PC can be counted as the most widely used variety of engineering plastics in the packaging category. The reason for this is that the use of drinking bucket production was developed. PC is one of the most in demand varieties of engineering plastics. But beyond that, PC has not found more use in packaging.
        PVDC, EVOH and nylon: as barrier plastic packaging and paper bag machine packaging materials,
        PVDC, EVOH, and nylon appear primarily as composite materials in the packaging category. Among them, EVOH and nylon films are mostly used for composite materials, instead of aluminum foil as barrier layers, but the scope of application is not very wide. As a relatively common barrier material, PVDC is mainly used for coating. The biggest application in our country is to make cigarette films, but it is also widely used in food.
        Third, the development trend of the main plastic packaging and paper bag machine packaging products
        Plastic packaging and paper bag machine packaging products have a complex variety of products, which can generally be divided into films, bags, bottles, large hollow containers, shallow trays and pallets. Each packaging shape is divided into many varieties because of its different uses and materials.
        Fourth, the cling film will be functionalized
        Plastic cling film is the most used film packaging material. At present, the variety of cling film in my country is still relatively small, and the varieties of cling film that are capable of grease, high temperature resistance, and suitable for functions such as microwave heating will continue to increase. In addition to PE, the amount of PVC and polyolefin cling film will increase. The development status of stretch film and heat shrinkable film is also similar.
        5. Shopping bags are developing towards degradable plastics
        Vest-style shopping bags are the most commonly used plastic packaging and paper bag machine packaging, often made of PE materials.
        Due to the large amount of shopping bag used, it is a one-time use packaging, therefore, it is one of the primary components of packaging discards.
        It is difficult to recover and the value of recovery is low, which is the primary reason for the relatively difficult recovery of plastic shopping bags. Therefore, the use of biodegradable degradable plastics is an ambition to solve the environmental pollution caused by abandoning shopping bags. How to rapidly degrade under composting conditions is the key to skill, and the functions of cost and warranty period are two important elements for whether degradable plastic can replace traditional shopping bags on a large scale.
       High barrier flexible packaging is the development trend
       The development of flexible packaging with high barrier properties for food and medicine will be accelerated. As the primary substrate, the production of BOPP film will gradually develop into multi-layer co-extrusion, and 3-layer and 5-layer films will be more widespread. At the same time, PET film will replace BOPP film in more fields because of its better barrier properties.
        The use of PVDC, nylon and EVOH barrier films will gradually increase. Especially PVDC composite film will be more widely used in the field of food packaging.
        In addition, many multi-functional composite films will be further refined in function, for example, special treatment of PP can be made into moisture-proof film, anti-condensation film, steam-proof film, adjustable moisture film and other types; special PE film can be made Corrosion-resistant film, mothproof film and non-slip film, etc.; while the two-way stretch nylon 66 heat-resistant film can achieve a higher heat resistance temperature than the two-way stretch nylon 6 film, and can withstand high temperatures of 140°C; the non-crystalline nylon film is transparent Similar to glass, it can preserve the color, aroma and taste, and adhere to the nutrient policy of the inner food and the stability of the taste quality.
        Six, plastic textile bags will be gradually reduced
        Plastic woven bags are made of plastic film, mainly polypropylene, into narrow belts of a certain width, or plastic flat belts with high strength and low elongation are obtained by hot stretching, and then these flat belts are woven. Plastic woven bags have much higher strength than plastic film bags, and they are not easy to deform and have impact resistance. At the same time, because the surface of the woven bags has woven patterns, it has a non-slip function and is convenient for stacking during storage. Plastic woven bags are mainly used for the packaging of food, cement, fertilizers and other commodities. However, due to the disadvantages of poor insect-proof and moisture-proof functions and large environmental pollution, the application in these areas is gradually being reduced.
        7. The market for water-based and solvent-free adhesives is endless
        In plastic composite plastic materials, water-based adhesives will be the direction of future development. Water-based adhesives now account for 50% of the flexible packaging composite adhesive market in the United States. In the European market, solvent-free adhesives account for 40% of the composite adhesive market. As people’s awareness of environmental protection has increased and environmental regulations have become more stringent, in the next ten years, environmentally-friendly water-based and solvent-free adhesives will replace solvent-based adhesives and become mainstream products.
        8. Beverage containers are developing towards low cost and high functionality
        The space for reducing the weight of PET bottles used for carbonated drinks and bottled water is now very small. The future development is mainly to increase the speed of production equipment. With the advent of the age of cold aseptic filling of beverages, the general PET bottles are making a comeback. At the same time, the technology of using recycled materials as the core layer in the production of general PET bottles has been appropriately sophisticated. However, due to the high demand for equipment, the cost has become the primary factor restricting development.
        The bottleneck crystallization technology of hot-filled PET bottles is the key. Now the latest technology can make the bottle tolerate the filling temperature of 93℃, although from the viewpoint of sterilization, higher temperature may not be necessary. The future development trend of hot-filled bottles mainly focuses on reducing weight and developing more bottle types.
        The development of plastic beer bottles has undergone several processes such as adding PEN and applying barrier coatings. The more feasible plan now is to use multilayer bottle production technology, and the center uses EVOH or nylon as the barrier layer. However, due to factors such as cost, it is not clear when this market will be launched.
        PC is now the primary material for making 5-gallon drinking buckets. It has been reported that drinking buckets made of PET can also meet the quality requirements, but in a short time, PET still has no possibility of replacing PC.
        As a newly developed product, BOPP bottles are now mainly concentrated in some beverages that require high temperature sterilization or pasteurization, such as herbal tea.
        Its most important application areas are now concentrated on large infusion products.
        PE containers are not used much in beverage packaging, and are mainly concentrated in a small amount of large-capacity (such as 5 liters) bottled water.
        9. Plastic bottles for medicine and cosmetics
        Unlike the PET bottles produced by the injection stretch blowing technique for beverages, the bottles for medicine and cosmetics are mostly extruded PE bottles, especially bottles for cleaning products. Nowadays, transparent bottles are becoming more and more popular. However, most of the shampoo bottles are still unclear PE bottles, but a single cap is replaced with transparent PP raw materials. In the future, high-transparency PP bottles and PET bottles will be used more in the packaging of shampoo and hair care products.
        Medical plastic bottles are mainly made of PE and PP, because it is necessary to consider protection from light, the use of PET bottles in this field is bound to be restricted. However, the general trend is to use more and more. Some manufacturers that produce low- and medium-speed PET equipment have now locked their policy on pharmaceutical packaging.
        X. Hollow containers are becoming larger and more multi-layered
        Plastic hollow containers of more than 100 liters are now widely available. Domestic equipment can now be produced and meet the demand. The 200-liter PE drum can even meet the requirements of the Class II maritime dangerous regulations, instead of the 200-liter silent steel drum. There are also several domestic companies producing PE plastic barrels of more than 1 ton. The promotion and application of this packaging barrel is expected to make it the primary method of packaging for professional liquids such as petrochemicals and chemicals.
        In addition, large-scale hollow containers are developing in the direction of double-layer and multi-layer co-extrusion.
        11. Plastic trays, yogurt cups and plastic trays
        The application of plastic trays is becoming more and more extensive, such as in fast food. Most of these trays are made of PP and can be used in microwave ovens. In addition, PP sheet is also the primary raw material for making yogurt cups. However, high-grade yogurt cups tend to be made with PS sheets.
        Plastic pallets are light, water-resistant, not easily affected by insects, beautiful, neat, and can be used repeatedly, which is good for outdoor work and storage. Compared with wooden pallets, its hardness and turnover rate can be increased by 3-5 times.

        Plastic pallets have two types: single-sided and double-sided, and double-sided are divided into two types: integral and assembled. At present, domestic plastic pallets are most commonly used for injection molding, followed by extrusion-hollow blow molding. Extrusion molding products are not used much, and vacuum suction molding is rarely used.