Polyethylene What are the main components of polypropylene and how to granulate

Polyethylene is formed by polymerization of ethylene monomer; Polypropylene is made by polymerization of propylene monomer. Extrusion granulation by heating the extruder. Buy an extrusion granulator and you can produce.

Copolymer of ethylene with a small amount of olefins.

Summary. The principle of propylene polymerization into polypropylene: under the action of the initiator, it is formed into CH3-CH+-CH2, and the electrophilic addition reaction of another propylene is attacked to obtain CH3-CH+-CH2-CH(CH3)-CH2, which can be further chained to form polypropylene, and the -CH2 at the end can be combined with each other to form a longer chain, and finally the reaction is terminated under the action of the reducing agent.

The process by which propylene is formed into polypropylene.

The principle of propylene polymerization into polypropylene: under the action of the initiator, it is formed into CH3-CH+-CH2, and the electrophilic addition reaction of another propylene is attacked to obtain CH3-CH+-CH2-CH(CH3)-CH2, which can be further chained to form polypropylene, and the -CH2 at the end can be combined with each other to form a longer chain, and finally the reaction is terminated under the action of the reducing agent.

Propylene polymerization reaction process.

The reaction equation of propylene polyaddition is CH3-NCH3CH=CH2——-CH-CH2-]-N.

Carbon tetrachloride is used as the solvent and azodiisonitrile is used as the initiator to chlorinate the polypropylene at a certain temperature, and the chlorinated polypropylene with chlorination of 35 can be prepared. Its viscosity is 370MPa S and its pH is 7 2

Produced by chloroform solvent method, polypropylene is dissolved in solvent, and then chlorine gas is introduced for chlorination reaction, chlorinated polypropylene solution is obtained after the solvent is removed from the chlorinated solution, and the chlorinated polypropylene solution is dried and granulated to obtain chlorinated polypropylene products, wherein the solvent used is chloroform, chloroform is used as a solvent to produce chlorinated polypropylene, which is more conducive to the full dissolution of polypropylene in chloroform, can reduce the dissolution time and chlorination time, improve production efficiency, and at the same time, is also conducive to improving the chlorination effect, It is relatively more environmentally friendly, and the color, stability and aging resistance of the chlorinated polypropylene products produced are better.

Polypropylene is used as raw material and toluene is used as solvent. The chlorination modification process of polypropylene was studied with azodiisobutyronitrile as the initiator, and the effects of chlorination temperature, initiator dosage, chlorination time and C12 gas flow rate on the chlorination degree of polypropylene were investigated. The results showed that the suitable chlorination temperature was 88 93, the mass fraction of initiator was 0 1, the reaction time was 200 min, and the cl2 gas flow rate was 180 ml min

After comparing and demonstrating the characteristics of solvent method, solid phase method, semi-aqueous phase method and aqueous phase method, it is considered that the aqueous phase method has the significance of promotion in China.

If you want to test whether the imported propylene is pure, I recommend a method to try, (but I don't know your company's conditions?) So we can only talk about theories).Because there are double bonds in the propylene molecule, the oxidation reaction occurs on the double bonds, and the cold and dilute potassium permanganate alkaline or neutral solution is used as an oxidant, and the bonds of propylene are opened to form o-diol compounds, and at the same time, the purple-red color of the potassium permanganate solution immediately fades.

This is a method for identifying unsaturated hydrocarbons. It's called the Bayer test.

If the acidic solution of potassium permanganate is used as an oxidant, not only the bond is opened, but also the Sigama bond is broken, and not only the double bond is oxidized, but also the carbon-hydrogen bond directly connected to the double bond is also oxidized. Depending on the structure of the olefin, the oxidation products are also different.

For example, R-CH2 = CH2 (double bond at the end of the carbon chain) plus potassium permanganate acidic solution to form carboxylic acid and formic acid, which in turn is oxidized by oxygen atoms to carbon dioxide and water.

If the double bond is in the middle of the carbon chain, and three different R groups are joined under the same conditions, carboxylic acids and ketones will be formed, and the molecular structure of the olefin can be inferred by identifying the oxidized products. Because the olefin molecule with carbon dioxide and water should have a ch2 = group in the molecule; The product is a carboxylic acid should have r-ch=group; The product is a ketone (R1, R2)-C= group (to note, R1 and R2 are different hydrocarbon groups attached to carbon atoms containing double bonds) As long as the structure of the oxidation product is removed and the oxygen atom is reconnected, it will be reduced to the original olefin structure. If you are propylene here, the structural formula should be ch3-ch2=ch2, then the double bond is at the end of the carbon chain.

I don't know if it will meet your needs.

【Raw materials for the production of polypropylene】The main raw material is propylene, and polypropylene is made by polymerization of propylene by adding some stabilizers by ionic polymerization.

propylene, CH2=CHCH3), a colorless, slightly sweet gas at room temperature. Molecular weight, density, freezing point, boiling point. It is slightly anesthetic, and it is completely decomposed under 815.

Flammable, ** limit of 2% to 11%. Insoluble in water, soluble in organic solvents, is a low-toxicity substance. Propylene is the basic raw material of the three major synthetic materials, mainly used in the production of polypropylene, acrylonitrile, isopropanol, acetone and propylene oxide.

It is prepared by copolymerization of ethylene with propylene, butylene and other second monomers.

A thermoplastic resin prepared by polymerization of propylene.

Polyethylene plastic greenhouse, polyvinyl chloride wire outer plastic layer, polybenzene lighting shell,

Polyethylene for food bags, food packaging films.

PVC artificial leather, wire packaging material.

I don't know about those two

1. Plastic steel fiber.

It is a new type of synthetic fiber. The product is mainly made of polypropylene and polyethylene as raw materials, which are synthesized by special processing, combining the advantages of steel fiber and plastic synthetic fiber, and is mainly used to replace the welded metal grid and steel fiber in the concrete panel structure.

2. Propylene film.

According to statistics, the world's plastics used in the packaging field account for about 35% of the total consumption of plastics. China's packaging plastics have developed rapidly, the output has increased rapidly from 190,000 tons in 1980 to 4.65 million tons in 2003, and is expected to exceed 5.5 million tons in 2005, more than 6 million tons in 2010, and more than 6.5 million tons in 2015, accounting for more than 13% of the total packaging output in the country.

Polypropylene is made of high-purity propylene as monomer, titanium trichloride as the main catalyst, monochlorodiethyl aluminum as the co-catalyst, gasoline as the solvent, hydrogen as the molecular weight regulator, continuous polymerization in the polymerization kettle at a certain temperature and pressure, polymer is a suspension, washed, separated, dried or extruded granulation by methanol esterification, and the finished product of granular or powdered homopolymer or copolymer is obtained, which is polypropylene.

Polypropylene resin is a milky white granular or powder product that is odorless, tasteless and non-toxic, with excellent mechanical properties, heat resistance, electrical insulation properties, good chemical stability, and does not interact with most chemicals. However, the light fastness is poor, the impact strength is poor at low temperature, and the dyeing is poor, so it needs to be improved by adding additives, blending, copolymerization and other methods. It is insoluble in water, does not absorb water, can be boiled in water, and is easy to process and shape.

It can be used as fan motor cover and electrical insulation material, can be used as household appliances such as TV and radio shell, can be used as anti-corrosion pipes, plates, storage tanks and equipment linings, building materials, special grades can be used to make washing machine barrels, infusion bottles, etc., and can also be used to make woven bags, packaging films, strapping materials and various containers, and can also be used to produce fibers.

In automobiles, it can be made into instrument panels, door panels, bumpers, door posts, pedals, fenders, bottom guards, etc.

Rice cooker shell base, washing machine shell, and so on.

Lock-up cups, semi-transparent lunch boxes, and so on.

It is better to use polyacrylamide, and good polyacrylamide is generally non-toxic and non-polluting, and it is very good for the human body and the environment Diethanolamine.

Polypropylene is a crystalline polymer with a crystallinity of up to 50-70% and a relatively obvious melting point of 164-170 degrees. The thermal stability is good, the decomposition temperature can reach more than 300 degrees, and the resin begins to turn yellow at about 260 degrees when in contact with oxygen. The melt fluidity of polypropylene rocker arm polyethylene is good, which shows the relationship between barrel temperature and flow length and the relationship between injection pressure and flow length, respectively.

The degree of decline of melt viscosity with the increase of injection temperature and pressure is more obvious than that of HDPE, and the influence of pressure on melt viscosity is more significant than that of temperature. The melt has large elasticity and fast cooling and solidification speed, which is easy to produce internal stress, and the molding shrinkage rate is relatively large (and has anisotropy, so it is necessary to pay attention to the design of products and molds. Polypropylene has strong molding adaptability, and can be used in general injection molding machines, but due to its low density, there is an equipment capacity problem that needs attention, and the weight of the product is usually required to not exceed 50-60% of the equipment capacity, so as not to cause problems such as insufficient products.

For polypropylene, colorants can not only increase the beauty of the product, but also have a certain effect on the performance of the product, such as carbon black can improve its lightfastness.

However, if the selection is improper, it will be counterproductive and harmful to the products, such as phthalein pigments on the aging of polypropylene, which has a certain inhibitory effect in the early stage, but the extension of time promotes the aging of products, so it is allowed to consider carefully and choose carefully in use. Polypropylene has outstanding folding properties, so it is often used to make various hinge (also known as hinge) products. Since the folding performance depends to a large extent on the rationality of the mold structure, it is necessary to pay attention to the quality of the mold design.

The combination of polypropylene's excellent flow properties and wide range of flow rates, as well as other unique polymer properties, gives it excellent processability. There are many methods of molding, including injection molding, blow molding, vacuum thermoforming, coating, rotational molding, electroplating and foaming, as well as spraying on metal surfaces. Among them, the proportion of injection molding is large, and in order to prevent shrinkage and deformation caused by post-crystallization, the products generally need to be soaked in hot water.

Using the tubular water cooling process, PP can be processed into co-extrusion, blown film, and single-layer film. PP can also be extruded into tubular products such as beverage straws and drinking water pipes. There are also uses for PP** cable coatings.

In general, low-flow formulation materials are used to produce thick-walled products and those that require toughness. High flow rate materials are used to produce thin-walled parts and products that require fast processing, and polypropylene's excellent flow properties and wide range of flow rates, combined with other unique polymer properties, give it excellent processability.

Polyethylene: Flat zigzag Polypropylene: spiral structure, polyethylene Advantages:

Low temperature resistance, solvent resistance, toughness, good dielectric and electrical insulationPolypropylene advantages: boiling water resistance, steam resistance, solvent resistance, good dielectric and electrical insulationPolyethylene disadvantages: small bearing capacity, flammable, poor weather resistance.

Disadvantages of polypropylene: poor toughness, cold resistance, dyeability, and dimensional stability.