Supply ppr pipe processing pert warm tube production in Shandong the Matilda tube industry 

 Supply ppr pipe processing pert warm tube production in Shandong the Matilda tube industry 
 The PPR-chemical structure 

 PP random copolymers generally contain 1 - 7% (by weight) of ethylene molecules, and 99 - 93% (by weight) of propylene molecules. In the polymer chain, the ethylene molecules regularly inserted in the middle of the propylene molecules. In such a random or statistical copolymers, the majority (usually 75%), ethylene is a single molecule inserted combined into groups, called X3 (three consecutive ethylene [CH2] in order of priority in the main {TodayHot} chain), which can also be seen as an ethylene molecule inserted in the middle of the two propylene molecules. 

 Another 25% of ethylene is inserted in the multiple molecular binding into the main chain, also known as X5 groups, with five consecutive methylene group (two ethylene molecules inserted in the middle of the two propylene molecules). It is difficult to distinguish between X5 and higher groups, such as X7 and X9. In view of this, XS and higher ethylene content of the groups together statistics> X3,%. 

 The degree of randomness ratio X3/X5 can be determined. When the percentage of the groups X3 will significantly reduce the copolymer crystallinity This final performance impact of the random copolymer. Extremely high levels of ethylene copolymer polymer crystallinity, similar to the role when the content of atactic polypropylene. 

 Random PP copolymer is different from the homopolymer, random insertion of the ethylene molecule in the polymer main chain hinder the crystalline arrangement of the polymer molecules. The degree of crystallinity of the copolymer reduce the cause of changes in physical properties: random copolymers and PP homopolymers compared to the stiffness reduction, increased impact resistance, transparency and better. Ethylene copolymer, low melting temperature, which became their advantages in the application of certain aspects of 

 Random copolymer containing more leather extract and atactic PP, and much higher ethylene content of the polymer chains. This high leather extract content, depending on the polymerization process, to varying degrees in all the goods copolymer materials, and meet the Federal Food Administration (FDA) regulations for food contact the {HotTag} caused difficult. 









 The PPR-manufacturing method 

 Ethylene / propylene random copolymer is the simultaneous polymerization of ethylene molecules and propylene molecules in the system, the reactor and the production of PP homopolymer. Ethylene molecule is smaller than the propylene molecule (reactivity, the reaction is faster than about ten times) propylene. This allows the stereotactic weakening of the catalyst while the activity increases, resulting in the increase in atactic polypropylene production. In order to reduce the generation of random things, the need to reduce the reaction temperature, thereby reducing the activity of the catalyst and reduce the random isomer of the final product, to get a more balanced performance products. 

 Deal with high ethylene content (> 3%) random copolymer in the production process more difficult, it is difficult to polymerization in hexane diluent, because the two by-products of the reaction (atactic polypropylene containing ethylene content high copolymer) can be dissolved in hexane. This is the same in the body of liquid propylene polymerization, despite the low solubility. A large number of by-product of the the out of the of hexane dilution process production, must be separation come out in the the hexane recirculation stage, This will increase the the the total the cost of production,, however was able to to get the the of cleaner polymer to co-a small amount of soluble fraction of the. In the bulk polymerization process, these impurities will remain in polymers, and trouble in dealing with the thin sheet material. Moreover, the final copolymer products contain more soluble impurities. The use of organic solvents to a second washing can remove most of the impurities, but will increase the total cost of production of the copolymer. In general, high levels of byproduct flake random copolymer will become more sticky, when the ethylene content higher than 3.5% (weight), the problem is more prominent. 

 The copolymer melting point lower and directly related to the ethylene content. It is reported that the ethylene content of 7%, the copolymer of the low melting point of 152 ° F. X3 content of the copolymer melting point greater than the child and the impact of the higher gene content. It also depends on the catalyst itself, instead of the combination of ethylene groups in X5 X3 groups.