Study on PBT Flame Retardant Modification

The production technical route of polybutylene terephthalate can be divided into direct esterification method and transesterification method. The product is milky white translucent to opaque, crystalline thermoplastic saturated polyester. It has high heat resistance, toughness, fatigue resistance, self-lubricating, low friction coefficient, weather resistance, low water absorption, only 0.1%, maintains various physical properties (including electrical properties) in a humid environment, electrical insulation Resistance to hot water, alkalis, acids, oils. But it is easily corroded by halogenated hydrocarbons, has poor hydrolysis resistance, can crystallize rapidly at low temperatures, and has good moldability. The disadvantage is that the notched impact strength is low and the molding shrinkage rate is large. Therefore, most of them are reinforced by glass fiber or modified by inorganic filling, and its tensile strength and bending strength can be increased by more than one time, and the thermal deformation temperature is also greatly increased. It can work for a long time at 140°C.

In order to achieve safe flame retardantrequirements, flame retardants need to be added to PBT. Flame retardants mainly include halogen, phosphorus, inorganic and melamine compounds. Among them, brominated flame retardants occupy an important position in the flame retardant technology of plastics with their best comprehensive performance. Now, with the increasing requirements for environmental friendliness, halogen-free flame retardant technology has become the focus of attention.