詳細(xì)內(nèi)容：PC FXE1112T}PC FXE1112T PC FXE1112T}PC FXE1112T LLDPE The tensile property and LDPE ratio of LLDPE, the tensile number and tensile yield strength are large, especially the tensile fracture strength and elongation at break. Generally, the energy needed for fracture is obtained from the stress-strain curve area, which is used as an index of resin rigidity. Obviously, LLDPE good rigidity, it can be considered as the reason for tethering LLDPE molecule. The relationship between rigidity and density: the lower the density, the worse the rigidity (or softer). As far as the same density is concerned, the impact strength of LLDPE is larger, and the impact strength of C6 and C8 copolymers is higher than that of C4. The physical and mechanical properties of LLDPE film are obviously superior to that of LDPE, and their softness, toughness, cold resistance and puncture resistance are better than that of LDPE. Futures /LLDPE LLDPE (linear low density polyethylene) Trading unit: 5 tons / hand Quotation unit: yuan (RMB) / ton Minimum change price: 5 yuan / ton The price limits: on a trading day settlement price 4% Contract month: 1 to December Trading hours: Monday to Friday (except Beijing time legal holidays) 9:00-11:30 p.m. 13:30-15:00 Last trading day: the tenth trading day of the month of the contract Last delivery day: the last trading day after second days Delivery grade: quality standard of linear low density polyethylene delivery for Dalian Mercantile Exchange Delivery location: the Dalian Mercantile Exchange linear low density polyethylene designated delivery warehouse Minimum transaction margin: 5% of the contract value Transaction fee: no more than 8 yuan / hand Way of delivery: physical delivery Transaction code: L Stock Exchange: Dalian Mercantile Exchange brief introduction Polyethylene (PE) is one of the five largest synthetic resins. Polyethylene is mainly divided into three categories: linear low density polyethylene (LLDPE), low density polyethylene (LDPE) and high density polyethylene (HDPE). 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. PBT but also produce HDPE by adding comonomers, also known as linear low density polyethylene. In recent years, various low pressure processes have developed rapidly. Medium pressure only Philip company is still in use, the production is mainly high density polyethylene. The method of polymerization of ethylene into low density polyethylene by using oxygen or peroxide as a initiator in high pressure method. Ethylene through two stage compressed into the reactor (Figure 3), under the pressure of 100 ~ 300MPa, the temperature of 200~300 DEG C and under the action of the initiator for the polymerization of polyethylene, the reaction by decompression separation, the unreacted ethylene recovery after recycled polyethylene melt like in adding plastic additives after extrusion granulation. (see pictures) used in polymerization reactor has a tubular reactor (length of 2000m) and reactor two. The single pass conversion rate of tube method is 20% ~ 34%, and the single line annual production capacity is 100kt. The one way conversion rate of the reactor was 20% to 25%, and the single line annual production capacity was 180kt. The low pressure method is divided into three kinds of slurry method, solution method and gas phase method. In addition to the solution method, the polymerization pressure is below 2MPa. The general steps include the preparation of the catalyst, the polymerization of ethylene, the separation of the polymer and the granulation. 1. The polythene produced by the slurry method is insoluble in the solvent and is in the form of slurry. The slurry polymerization conditions are mild and easy to operate. Alkyl aluminum is used as activator, hydrogen is used as molecular weight regulator, and most of the reactor is used. The polymer slurry produced by the polymerization kettle passes through the flash kettle, the gas-liquid separator to the powder dryer, and then the granulation (Figure 4). In the process of production, the process of solvent recovery and solvent refining are also included. The products with different molecular weight distribution can be obtained by the combination of different polymerizer in series or in parallel. 2. The solution was polymerized in the solvent, but ethylene and polyethylene were dissolved in the solvent, and the reaction system was homogeneous solution. The reaction temperature (140 DEG C), high pressure (4 ~ 5MPa). Characterized by short polymerization time and high production intensity, it can produce three kinds of polyethylene with high density, medium and low density, which can control the properties of products better. However, the molecular weight of polymer obtained by solution method is low, and its molecular weight distribution is narrow and solid content is low. (3) the gas-phase polymerization of ethylene in the gaseous state is generally used as a fluidized bed reactor. The catalyst has two kinds of chromium and titanium, which are added into the bed by the storage tank. The high speed ethylene cycle is used to maintain the fluidization of the bed and eliminate the polymerization heat. The generated polyethylene is discharged from the bottom of the reactor (Figure 5). The pressure of the reactor is about 2MPa, and the temperature is 85~100. Gas phase method is the main way to produce linear low density polyethylene. Gas phase method saves solvent recovery and polymer drying process, and saves 15% of investment and 10% of operation cost than solution method. 30% of the investment for the traditional high pressure method, the 1/6 of the operation fee. Therefore, it has been developed rapidly. However, the gas phase method should be further improved in product quality and variety. Medium pressure is used as a chromium catalyst supported on silica gel. In the loop reactor, ethylene is polymerized under medium pressure to produce high density polyethylene (HDPE). The processing and application of available blow molding, extrusion, injection molding method, widely used in the manufacture of thin film, hollow fiber and other products, daily-use sundry goods. In actual production, in order to improve the stability of ultraviolet and oxidation of polyethylene and improve the processing and use performance, a small amount of plastic additives should be added. The usual ultraviolet absorbent is two benzophenone or its alkoxy derivatives, and carbon black is an excellent UV shielding agent. In addition, antioxidants, lubricants, colorants and so on, so that the application of polyethylene to expand the scope of [1].