What is the main material of ppr tube

- Feb 29, 2020-

What is the main material of ppr tube

PPR (polypropylene random), also known as random copolymer polypropylene (PPR), has good toughness, high strength, excellent processability, good creep resistance at higher temperatures, and has the unique high transparency of random copolymer polypropylene Advantages, can be widely used in the production of pipes, sheets, daily necessities, packaging materials, household appliance parts and various films. The English name of PP-R is polypropylene random (copolymer). PP-R is the abbreviation of polypropylene random copolymer. It is also used to refer to the special conveying material for cold water pipes and hot water. PP-R pipe is also called type III polypropylene pipe, random copolymerized polypropylene. Random copolymerized polypropylene can be extruded into pipes. PP random copolymers generally contain 1 to 7% by weight of ethylene molecules and 99-93% by weight of propylene molecules. On the polymer chain, ethylene molecules are randomly interposed between propylene molecules. In this random or statistical copolymer, most (usually 75%) of the ethylene is incorporated by single molecular insertion, which is called X3 group (three consecutive ethylene [CH2] are arranged in order in the main {TodayHot} chain), this can also be seen as an ethylene molecule inserted between two propylene molecules. Another 25% of ethylene is incorporated into the main chain by multi-molecular insertion, also known as X5 group, because there are 5 consecutive methylene groups (two ethylene molecules are inserted together between two propylene molecules). It is difficult to distinguish X5 from higher groups such as X7, X9, etc. In view of this, XS and the ethylene content of higher groups are counted together as> X3%. The randomness ratio X3 / X5 can be measured. When the percentage of groups above X3 is large, the crystallinity of the copolymer will be significantly reduced, which will greatly affect the final performance of the random copolymer. The effect of very high levels of ethylene in the copolymer on the crystallinity of the polymer is similar to the effect at high random polypropylene levels. Random PP copolymers are different from homopolymers because the ethylene molecules randomly inserted into the polymer backbone hinder the crystalline arrangement of the polymer molecules. The decrease in copolymer crystallinity causes a change in physical properties: random copolymers have lower stiffness, improved impact resistance, and better transparency than PP homopolymers. Ethylene copolymers also have lower melting temperatures, which is an advantage when they are used in some applications. Random copolymers contain more leather extractables and random PP, as well as polymer chains with much higher ethylene content. This higher content of leather extracts, depending on the polymerization process, is present in all commercial copolymer materials to varying degrees and is caused by meeting the Federal Food Administration's (HotTag) regulations for food contact difficult.