plasticizer
DATE：2022/3/31 9:08:57 / READ： / SOURCE：This station
plasticizer
The purpose of adding plasticizer has two kinds, one is to improve the processing performance of polymer. Expand the temperature range of processing molding, such as reducing the flow temperature of the polymer T, to expand the temperature range of polymer viscous flow state, easy to extrude injection molding. The other is to improve the performance of the polymer, such as reducing the glass temperature of the polymer to room temperature below, so that the product has a certain softness at room temperature. Corrugated board equipment www.handern.com1. Plastizing principle polymer is composed of many macromolecular chains, there is interaction between macromolecular chains, this physical force comes from van der Waals force and hydrogen bond, also known as secondary valence force, its large, and the molecular structure of the polymer performance. The intermolecular forces that make the polymer Strength, but also affect its processing performance, thermoplastic processing essence is by adding to increase the activity of polymer molecules, in order to weaken the intermolecular force, so that the polymer has plasticity. However, for some polymers with large intermolecular force and thermal instability, it is more difficult to make it have the plasticity required for processing. Take PVC as an example, PV is a strong polar polymer, there is a great intermolecular force, which needs to be heated to more than 160℃ to appear plasticity, but on the other hand, PVC is very sensitive to heat. When heated to 130 ~ 140℃, thermal decomposition begins, so plastic molding cannot be carried out. The role of plasticizer is to weaken the intermolecular force of the polymer, thereby reducing the softening temperature, melting temperature and glass temperature, the viscosity of small melt, increase its fluidity, improve the flexibility of polymer processing and products. There are a variety of plasticizer mechanism, it is generally believed that plasticizer inserted between polymer molecules, weaken the intermolecular force, it can play the role of plasticizer. Accordingly, often use two kinds or a variety of plasticizer to use at the same time, in order to learn from each other, receive better practical result. Corrugated board equipment www.handern.com
2. Commonly used plasticizer. It is a lot of varieties of plastic, in the desire to think in the use of PvC to increase the benefit of the most. PvC commonly used plasticizer according to the chemical structure classification is introduced as follows :(1) phthalic acid ester this kind of plasticizer can be compatible with a lot of polymers, easy to mix evenly, the stability of heat and light are good. One of the more widely used bis (2 ethyl hexyl) phthalate (DOP). There is a special odor of dioctyl ester, colorless or light yellow sleeve transparent liquid. Its advantages: high plasticizing efficiency, small volatility, small mobility, water resistance, uv resistance, good cold resistance, softness and electrical properties, is an ideal plasticizer. Suitable for PVC, vinyl chloride copolymer, cellulose resin, synthetic rubber and so on. Because its toxicity is very small, can be used to contact with food (except fatty food) foam plastic products; Diisooctyl phthalate (DIOP) is also a better plasticizer, its performance and DOP are roughly the same, but the electrical properties, plasticizing efficiency, low temperature resistance slightly worse. It can be used as the main plasticizer of PVC, oxyethylene copolymer, cellulose resin and rubber, especially suitable for plasticizing PVC paste; Diisodecyl phthalate (DIDP), this viscous oily liquid, volatile, migration resistance, extraction resistance and electrical insulation is very good, but the compatibility with the polymer is poor, plasticizing efficiency and cold resistance are not as good as DOP.
(2) phosphate ester such plasticizers are mostly toxic, but the flame retardant is better. Trimethylbenzene phosphate (TCP) is a clear viscous liquid with a slight odor. It has good compatibility with cellulose acetate, ethyl cellulose, PVC, PS, phenolic resin, etc. It has good flame retardancy and hydrolysis stability, excellent oil resistance and electrical insulation, and high bacterial resistance. But cold resistance is poor, and toxic; Tri (butyl-ethyl) phosphate is a yellow or colorless liquid with excellent low temperature flexibility, flame retardant and durability. It can be used for cellulose nitrate to make transparent flexible film. Its migration is larger, toxic. Can be used for PVC, polymethyl methacrylate (PMMA), cellulose acetate, cellulose nitrate and other compatible. (3) adipic acid ester such plasticizer can withstand low temperature. Dioctyl adipate (DOA) is a colorless, transparent, oily liquid with a slight odor. It is a typical cold resistant plasticizer. Plasticizing efficiency is high, heat discoloration is small, have good low softness softness and light resistance. This plasticizer can also play a lubricating role during processing, and the products produced feel good. But its volatility, water resistance, resistance to migration, electrical insulation and other poor. This kind of plasticizer can be used for PVC, vinyl chloride copolymer, PS, cellulose nitrate and other raw materials; Adipic acid 2 isooctyl ester (DIOA), also is a kind of cold resistant plasticizer, is colorless oily liquid, performance and applicable raw materials and DOA close, better electrical performance, low volume resistance, antistatic action, can be regarded as non-toxic. (4) sebacic acid ester such plasticizer cold resistance is also better, sebacic acid two octyl ester (DOS), is yellow or colorless transparent oil liquid, is excellent cold plasticizer, has good heat resistance, light resistance and electrical insulation. High mobility, poor water resistance, PVC, vinyl chloride copolymer, cellulose nitrate and other efficient plasticizer. Corrugated board equipment www.handern.com
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