PBT is one of the latest and fastest-growing varieties of engineering plastics in plastics industry. With its excellent overall performance, good moldability and cost performance, excellent mechanical properties, high mechanical strength, fatigue resistance and dimensional stability, Change is small. These properties are rarely changed under high temperature conditions, is ideal for automotive, electronics and other fields, and today we understand the application of PBT materials.
First, the history of development
1942 German scientists P.Schlack developed into PBT resin, after the United States Celanese Corporation (now Ticona) for industrial development, listed under the Celanex trade name
1970 30% glass fiber reinforced plastic on the market, trade name X-917, later changed to CELANEX
1971 Eastman company has introduced glass fiber reinforced 琏 and non-enhanced products, trade names Tenite (PTMT)
1971 GE company also developed similar products, there is no enhancement, enhancement and self-extinguishing of the three varieties.
Then the world-renowned manufacturers Germany BASF, Bayer, the United States GE, Ticona, Japan Toray, Mitsubishi Chemical, Taiwan Shin Kong Fibers, Changchun, South Asia Plastics and other companies have put into the ranks of production.
Second, the performance
Excellent mechanical properties, especially high rigidity and hardness
Good heat resistance, heat distortion temperature up to 180 ℃
Good surface gloss performance, especially for spray-free electrical and electronic products
Faster crystallization speed, good fluidity, good moldability
Good thermal stability, in particular, has a lower rate of thermal expansion and size shrinkage
Good resistance to chemicals, solvents, weathering
High dielectric strength, good electrical properties
Low hygroscopicity, minimal impact on electrical and dimensional stability
The molecules contain ester bonds, which decompose under the action of strong acids, bases and water vapor
Material is more sensitive to the gap, there is a brittle phenomenon
1. Enhance the modification
In the PBT add glass fiber, glass fiber and PBT resin bonding strength, PBT resin in a certain amount of glass fiber, not only can maintain PBT resin chemical resistance, workability and other original advantages, but also have a greater Improve its mechanical properties, and overcome the PBT resin gap sensitivity.
2. Flame retardant modification
PBT is a crystalline aromatic polyester, if not added flame retardant, the flame retardant are UL94HB grade, only by adding flame retardants, in order to achieve UL94V0 level.
Commonly used flame retardants are bromides, Sb2O3, phosphides and chlorides and other halogen flame retardants, the most is decabromodiphenyl ether, has been a major PBT flame retardants, but because of environmental reasons, European countries very early It is banned and all parties are looking for alternatives but have never had more performance advantages than alternatives to decabromodiphenyl ether.
3. Mixed alloy modified
The main purpose of PBT blended with other polymers: to improve the notched impact strength, to improve the warping deformation caused by shrinkage during forming and to improve the heat resistance.
Blend is widely used at home and abroad to modify it. Blends modified for PBT polymer mainly PC, PET, and so on. Such products are mainly used in automobiles, electronics, power tools, glass fiber in different proportions, and its application areas are also different.
Fourth, the application
With the popularization of lightweight automotive, engineering plastics in the automotive applications are also more and more, PBT as one of the engineering plastics with its excellent mechanical properties, mechanical strength, fatigue resistance and dimensional stability and other advantages in the car The application is also very wide.
Wipers, mirrors, door handles
New energy car charging gun
Home appliances and mobile phones
Black crystal furnace cover
Phone back shell
Electronic and electrical
PBT modified to have excellent toughness, high level of flame retardancy and good fluidity, excellent electrical properties of the electronic connector is the ideal material.
Solenoid valve shaft
With the upgrading of China's 5G communications network, PBT resin has been widely used in the field of optical fiber sheathing due to its excellent mechanical properties, water and moisture resistance, oil resistance, chemical resistance and electrical insulation.
PBT material as a lighting material has good heat dissipation and good price advantage, anti-aging, durable
LED heat lamp