pp/pc366-3特殊 系列pp 8181、pom as450、pbt ef1550gn30、tpe n95555、pc xht3141、pc/abs mc8800、pa6 fr50、pp 412mk49、pa12 aesng9t6l、
asa s253、abs d-150pei 3452、pc/abs t-2854、pc 9125、pp ep400m、petg gn310、tpe gn7155f 、lcp e6008、pp n00g-01 、
lcp 7140poe df610、pom s27072gv1/10、tpv a67bw
features are similar to pa12
pp/pc366-3特殊 系列pp r140n 、pa66 2020b、pa6 73m40、pc 3412r-131、pa6 g6-15、pa66 pa841、pp bj300、pp bf20h 、tpe pj6300c、
pc pz715、pc ln-2350sg qe0910npc/abs ne-1030、pc/abs 2-1473、pp n700p、eva ld-312、tpv 4475、pc d-ep8167、ppo px1005wh、pc dd000、
pp 7231x pp ep500n、pa6 6hv2fr、tpu ti75aa
pbt but also produce hdpe by adding comonomers, also known as linear low density polyethylene. in recent years, various low pressure processes he 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/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&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)&reactor two. the single pass conversion rate of tube method is 20% ~ 34%,&the single line annual production capacity is 100kt. the one way conversion rate of the reactor was 20% to 25%,&the single line annual production capacity was 180kt. the low pressure method is divided into three kinds of slurry method, solution method&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&the granulation. 1. the polythene produced by the slurry method is insoluble in the solvent&is in the form of slurry. the slurry polymerization conditions are mild&easy to operate. alkyl aluminum is used as activator, hydrogen is used as molecular weight regulator,&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,&then the granulation (figure 4). in the process of production, the process of solvent recovery&solvent refining are also included. the products with different molecular weight distribution can be obtained by the combination of different polymerizer in series/in parallel. 2. the solution was polymerized in the solvent, but ethylene&polyethylene were dissolved in the solvent,&the reaction system was homogeneous solution. the reaction temperature (140 deg c), high pressure (4 ~ 5mpa). characterized by short polymerization time&high production intensity, it can produce three kinds of polyethylene with high density, medium&low density, which can control the properties of products better. however, the molecular weight of polymer obtained by solution method is low,&its molecular weight distribution is narrow&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&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&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,&the temperature is 85~100. gas phase method is the main way to produce linear low density polyethylene. gas phase method ses solvent recovery&polymer drying process,&ses 15% of investment&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&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&application of ailable blow molding, extrusion, injection molding method, widely used in the manufacture of thin film, hollow fiber&other products, daily-use sundry goods. in actual production, in order to improve the stability of ultriolet&oxidation of polyethylene&improve the processing&use performance, a small amount of plastic additives should be added. the usual ultriolet absorbent is two benzophenone/its alkoxy derivatives,&carbon black is an excellent uv shielding agent. in addition, antioxidants, lubricants, colorants&so on, so that the application of polyethylene to expand the scope of [1].
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