I'm PP. People call me PP. Here's my resume
At present, polypropylene is very widely used and the output is very large. This article mainly from the introduction of polypropylene, history, classification, synthesis technology and domestic manufacturers, the main use and its brand, as well as the prospect of polypropylene seven aspects.
I. PE's sworn brother "PP"
PE has a brother called "PP", is a foreigner, the name is called "polypropylene", another name "PP", later came to China, do as the Romans do, took a Chinese name "polypropylene".It is very similar to PE,and they are thermoplastic body,.There is also no body odor, and the general foreigners are not like.However, the skin is rougher than PE, it feels harder, and the body is thinner(Light density is only 0.90 --" 0.91g /cm3, which is one of the lightest plastics),but higher than PE(One more methyl-CH3).In addition, the personality is more stubborn, how to play, how to fall, the heart does not beat, the eyes do not blink, the meat does not hurt, pat dust, and is a good man.(Folding glue, good recovery performance after deformation).
II.History of development
In 1953, Professor Karl Ziegler synthesized high crystallinity polyethylene for the first time.
In 1954, Professor Giulio Natta first synthesized crystalline polypropylene.
In the 1960s, the first generation Z/N catalyst period (active 1000kg/kg catalyst) slurry process technology was commercially produced;
In the 1970s, the second generation of Z/N catalyst appeared (active 10,000kg /kg catalyst), and the product isometric improvement began the research and development of bulk method and gas phase process technology;
In the 1980s, the third generation of Z/N catalyst was successfully developed (active 15000kg/kg catalyst), the product isotropy was further improved, and the products of random polymers were greatly reduced. Large-scale industrial plants were built using bulk method and gas phase method, as well as combination process technology.
In the 1990s, the fourth generation Z/N catalyst (active 60000kg/kg catalyst) improved the product form, produced high crystalline polymers, began to develop metallocene catalysts, and developed isotactic and syntactic polypropylene;
Brief description of the latest development, development of diether and succinate catalysts, development of ND catalysts.
III. Same face, different hairstyle
When it comes to the family, PP and PE are not the same. PE is according to weight (density) to speak, PP family ranking, it is not so strange. Because it is "triplets", the face is the same, the hairstyle is not quite the same. The elder brother is more gentle, the hairstyle is smooth, like a pot lid "equal rules"; Second is more fashionable, get a symmetrical hair, a long and a short "interval rule"; He was more spoiled, his hair was like killing Matt, and he was disorganized, and he didn't say anything at home.
(i). Isotactic polypropylene (isotactic polypropylene), abbreviated as IPP: each carbon atom containing methyl (-CH3) in the IPP molecule has the same configuration;
(ii). Syndiotactic polypropylene (abbreviated as SPP) : The carbon atoms containing methyl group (-CH3) in the SPP molecule are divided into two different configurations and alternate arrangement;
(iii). Random polypropylene (APP) : The methyl group (-CH3) attached to the main chain of APP is arranged randomly on both sides of the main plane.
IV. Place of birth and manner of birth
PP, like PE, grew up in a very poor family. Seniority is not as old as PE, but after decades of development, the size and number of the family are not lower than the PE family (output, manufacturers). Their descendants can usually have five ways to come to this world: solution method, slurry method, bulk method, gas phase method and bulk - gas phase combination process. At present, the more advanced methods in the world are mainly: gas phase process and body-gas phase combination process. (All of these processes use bulk, gas or a combination of bulk and gas processes to produce homopolymers and random copolymers, and then series gas reactor systems (one or two) to produce impact copolymers.)
V. Eat spinach and turn?(PP modification technology)
PP is a very smart young man, is a little glass heart(High brittleness, especially at low temperature), sometimes relatively high and cold(High crystallinity), can not stand too much grievance(Low molecular polarity), and others are not very fit in(Poor blending and adhesion with other polymers (such as plastics, rubber) and inorganic fillers), so the life circle is relatively small.However, eat spinach(modification), and suddenly, like a changed person, you can talk to a variety of people(Compatibility enhancement), you can also change like Ultraman, fight monsters(Strength enhancement), extinguish fires(Flame retardant modification), and steal other people's skills(graft modification).In short, the gods can't stop spinach.
1. Physical modification
1) Filling modification: Add a certain amount of inorganic filler and organic filler to PP to improve some properties of the product and reduce the cost of the material.
2) Enhancement modification: fibrous materials added to plastics can significantly improve the strength of plastic materials.
3) Blending modification: other plastics, rubber or thermoplastic elastomers can be blended with PP to prepare polymer alloys with these polymer properties;
2. Chemical modification
(1) Graft modification: PP graft modification is to introduce other groups in pp molecules, which can not only give PP some special functions, but also maintain the excellent characteristics of pp;
(2) copolymerization modification: refers to the modification of propylene monomer in the polymerization stage using catalyst;
(3) Crosslinking modification: In order to improve form stability, creep resistance, improve strength and heat resistance and melt strength, shorten the molding cycle.
VI. Popeye Saves the World (Specific Applications and brands)
After decades of development. PP has a certain understanding of its own ability. So, in his daily life, he slowly changes himself by exerting his abilities, thereby changing the world. Today, he is like the air (film, plastic bags, cups, chairs, auto parts, electronic appliances and other plastic products), permeated in people's lives, people can not live without his existence. Life can see, all have him, can not see the place (plastic pipe), still have him.
