LLDPE With the continuous improvement of people's living standard, it will inevitably bring different demands and improvements in all aspects of culture, entertainment, food, medical treatment, materials, room decoration and so on. More and more transparent materials are used in many markets. Therefore, the development of transparent PP special materials is a good trend, especially for PP special materials with high transparency, good fluidity and fast molding, so as to design and process PP products that are popular with adults. Transparent PP has more features than ordinary PP, PVC, PET and PS, and has more advantages and development prospects. In recent years, foreign transparent PP market is growing rapidly, such as South Korea will be transparent PP as PET alternatives to the market; some companies in Germany to replace PVC with a transparent PP transparent PP products; the growth rate is higher than the ordinary PP products 7%~9%; Japan in recent years PP nucleating agent the annual amount is about 2000t, if adding 0.25% projections, Japan transparent PP material up to the annual output of more than 800 thousand T. According to the Japanese physicochemical Co., Ltd., Japan's transparent PP special materials used in microwave cookers and furniture in two aspects of the largest consumption. It is expected that in 2005, the demand for transparent PP special materials in foreign markets is about 5 million ~550 million T. At present, the gap between foreign transparent PP special materials and foreign countries is large, and the production and application of transparent PP resin and its products still need to be strengthened. Other 1. uniaxial tensile PP films The process flow is as follows: proportioning, plasticizing, extrusion casting of T type head, cooling, corona treatment, traction, coiling, aging treatment, sub cutting, and finished products. The screw speed of 60 rpm, 180, 220, 240, the temperature of 250 DEG C, traction speed 80 m / min, and the cooling temperature of 30 DEG C, the surface tension of 42 dyn / cm. HDPE Product performance High density polyethylene is non-toxic, tasteless, odorless white granule, a melting point of 130 DEG C, relative density is 0.946~0.976g/cm3, it has good heat resistance and cold resistance, good chemical stability, also has high rigidity and toughness, good mechanical strength, dielectric properties, resistance to environmental stress cracking resistance is also good. Application It is used for extrusion packaging films, ropes, weaving nets, fishing nets, water pipes, injection moulds, lower grade daily necessities and shells, non load-bearing components, plastic boxes, turnover boxes, extrusion blow molding containers, hollow products, bottles. For blow molding products and film products such as food packaging bags, shopping bags, sundry goods, fertilizer lined film etc.. National standard Serial number item index LDPE LLDPE EVA HDPE Common environmental protection 1 thickness mm 0.2-3.0 0.2-3.0 0.2-4.0 0.2-4.0 2 width m 2.5-9.0 2.5-9.0 2.5-8.0 2.5-8.0 3 tensile strength (vertical and horizontal) Mpa More than 14 more than 16 >=17 >=25 4 elongation at break (vertical and horizontal)% >=400 >=700 >=550 >=450 >=550 5 right angle tearing strength N/mm >=50 >=60 >=60 >=80 >=110 6 water vapour permeability coefficient of G. cm/c.S. PA <1.0*10 <1.0*10 <1.0*10 m - -- 7 the temperature range of +70 DEG C -70 +70 DEG C -70 DEG +70 DEG -70 DEG C - -- 8 carbon black content% -- - -- - - 2.0-3.0 9 environmental stress cracking resistance F -- -- -- -- >=1500 Low temperature impact embrittlement at 10-70 C -- -- -- -- through pass Oxidation induction time at 11200 C -- - -- Main characteristics LDPE Low density polyethylene (LDPE), also known as high pressure polyethylene, is a plastic material. It is suitable for various forming processes of thermoplastic molding, with good processing performance. The main purpose of LDPE is to make film products, and also for injection products, medical equipment, medicine and food packaging materials, blow molding hollow molding products and so on. Sex low density polyethylene (English: Linear Low Density Polyethylene for short, LLDPE,) Linear low density polyethylene (LLDPE), is a senior of ethylene and alpha olefins (such as -1, -1, butylene hexene octenes methylpentene -1, four -1) in the presence of catalyst, a copolymer with high?or?low pressure polymerization, the density is between 0.915 ~ 0.940 g / cm3. However, according to the D-1248-84 of ASTM, the density range of 0.926 ~ 0.940 g / cubic centimeter belongs to medium density polyethylene (MDPE). The new generation of LLDPE expands its density to plastic (0.890 to 0.915 g / cubic centimeter) and elastomer (<0.890 g / cubic centimeter). But the American Plastics Industry Association (SPI) and the American plastic industry commission (APC) only extend the scope of the LLDPE to the plastic, not the elastomer. In the 80s of last century, union?Carbide and Dow Chemical referred to their early sales of plastically and elastomers as very low density polyethylene (VLDPE) and ultra-low density polyethylene (ULDPE) resin. The molecular structure of conventional LLDPE is characterized by its linear main chain, with only a small amount?or?no long branched chain, but contains some short branched chains. Without long branching chains, the crystallinity of the polymer is higher. Generally, LLDPE resin is characterized by density and melt index. The density is determined by the concentration of the copolymerized monomer in the polymer chain. The concentration of the copolymers determines the amount of short branched chains in the polymer. The length of a short branched chain depends on the type of the monomers. The higher the concentration of the copolymers, the lower the density of the resin. In addition, the melt index is a reflection of the average molecular weight of the resin, which is determined mainly by the reaction temperature (solution method) and the addition of the chain transfer agent (gas phase). The average molecular weight is independent of the molecular weight distribution, and the latter is mainly influenced by the type of catalyst. LLDPE was industrialized by union?Carbide in 1970s. It represents a significant change in polyethylene catalyst and process technology, making the product range of polyethylene expand significantly. LLDPE instead of free radical initiator and low cost gas phase polymerization instead of free radical initiator, instead of high cost reactor, in a relatively short period of time, it has replaced LDPE in many fields due to its excellent performance and low cost. LLDPE almost penetrates into all the traditional polyethylene markets, including films, mouldings, pipes and wire and cables. LLDPE products are nontoxic, tasteless and odourless, and are milky white particles. Compared with LDPE, it has many advantages, such as high strength, toughness, rigidity, heat resistance and cold resistance. It also has good resistance to environmental stress cracking and tear strength, and it can resist acid, alkali and organic solvents. In 2005, China's LLDPE production was 1 million 880 thousand tons, accounting for about 35.5% of the total output of PE, and 3 million 550 thousand tons of consumption, accounting for 33.8% of the total consumption of PE. It is expected that in the next 2~3 years, the consumption of LLDPE will continue to grow at about 8%. According to the current market price of 12000 yuan / ton, the market size of China's LLDPE has exceeded 40 billion yuan.