Studies On The Preparation And Properties Of Flame-retardant Reinforced PBT With High Comparative Tracking Index

Polybutylene Terephthalate(PBT) is a kind of five engineering plastics,which is widely usded in the fields of electronical , electrical equipments and home electronics.Flame-retardant Reinforced PBT has the properties of glass fiber(GF) reinforced PBT and perfect flame-retardancy which could fulfill the extremely strict request on product's safty.While the high comparative tracking index and no-halogen flame retardant reinforced PBT composite is the hotspot and difficulty on study.The effect of traditional flame retardant Dechlorane Plus(DCRP)/antimony trioxide(ATO) content on the flame-retardancy and mechanical properties of glass fiber reinforced PBT composite was investigated.By adding magnesium hydroxide(Mg(OH)2) and calcium oxide(CaO) into flame-retardant PBT/GF,comparative tracking index(CTI) improved. Meanwhile,the effect on the flame-retardancy and mechanical properties were investigated.It was found that with the increase of DCRP/ATO content,the flame redancy of PBT/GF was improved observably. When Dechlorane Plus/antimony trioxide content was 16 wt%,the vertical burning of PBT/GF reached rating of V0.The compound of Mg(OH)2 with DCRP/ATO had good synergistic effect on flame-retardancy and could significantly depress the smoke production rate of DCRP/ATO.Mg(OH)2 could improve the CTI but it could decrease the mechanical properties of PBT/GF.Although CaO decreased flame retandancy a little,but it improved the mechanical priorities and CTI;When the CaO content was lower than 3 wt%,vertical burning of PBT/GF reached rating of V0.When the CaO content was 2 wt%,the general priorities were the best.The effect of red phosphorus masterbatch RPM-540B flame retandant content on the flame-retardancy and mechanical properties of glass fiber reinforced PBT composite was investigated.By adding Mg(OH)2 and CaO into flame-retardant PBT/GF , comparative tracking index(CTI) improved. Meanwhile , the effect on the flame-retardancy and mechanical properties were investigated.It was found that with the increase of red phosphorus masterbatch content,the flame-retardancy of PBT/GF was improved observably.When red phosphorus masterbatch content was 14 wt%,the vertical burning of BT/GF reached rating of V0.The compound of Mg(OH)2 with red phosphorus masterbatch had good synergistic effect on flame-retardancy and could significantly depress the smoke production rate of red phosphorus masterbatch.Mg(OH)2 could improve the CTI but it could decrease the mechanical properties of PBT/GF.With 4 wt% Mg(OH)2 ,the mechanical properties decreased 50%.Although CaO decreased the mechanical properties a little,but it improved the flame-retardancy and CTI;When the CaO content was 2 wt%,the mechanical properties of PBT/GF reached the maximum.When the CaO content was 3 wt%,all properties of reinforced flame retandant PBT were the best.A new type organic phosphorus flame retardant CJ1002 was used to preparte the no-halogen flame retardant reinforced PBT composite with high CTI.The effect of organic phosphorus flame retandant content on the flame-retardancy and mechanical properties of glass fiber reinforced PBT composite was investigated.It was found with the increase of flame retardant , the flame-retardancy of PBT/GF increased.Then the CTI reached to 550V.Compared with other flame retardants,the CTI of PBT/GF which was added to CJ1002 was higher.In order to improve the CTI,CaO was used in CJ1002,but it decrease the mechanical priorities and flame-retardancy;The CaO maximum content should be 1%.When the content was over 1%,it could decrease the priorities of mechanical and flame retardant sharply;When CaO content came up to 2 wt%,the CTI of reinforced PBT composite reached to 600V;When Cao content was 1 wt%,the general priorities were the best.