In PVC cable, we usually adopt the method of adding flame retardant and flame-retardant plasticizer to achieve the effect of flame retardant and smoke suppression. The specific methods are as follows: (1) The use of flame-retardant plasticizer to replace the conventional plasticizer. For example, triaryl phosphate and alkyl diaryl phosphate are often used as plasticizers, which are thermally decomposed during combustion to produce volatile phosphoric acid, and can form a protective film on the solid surface to cut off contact with oxygen. Chlorinated paraffin can also be added as a synergistic plasticizer, the flame-retardant effect is better.
(2) adding antimony compounds, metal hydroxide and other inorganic flame retardants. Aluminum hydroxide, which is usually added, also has obvious inhibitory effect on smoke.
(3) The method of adding flame-retardant plasticizer, inorganic flame retardant and flame retardant filler was used at the high content of plasticizer.
(4) Smoking inhibitor is usually added. Mainly used for PVC cable materials smoke suppression of molybdenum trioxide and ammonium molybdate. In the formulation of PVC cable materials we often need to be based on different uses of cable materials and flame retardant requirements to choose the appropriate flame retardant plasticizer and the proportion of conventional plasticizers, so as to achieve a high cost-effective.