Preparation And Properties Of Laminates With Epoxy Resin Modified By Flexible Chain Blocking Hyperbranched Polyester

Faced with the high-speed transmission of information,there were higher requirements for many properties of copper clad laminate under high frequency conditions.Because of its special physical and chemical properties,hyperbranched polyester can effectively improve the comprehensive properties of copper clad laminates.In this paper,a kind of hyperbranched polyester?HBP-C?was prepared which with pentaerythritol was used as the nucleus of 2-dimethylol propionic acid as branching chain and n-butyric acid,n-hexanoic acid,n-octanoic acid and n-sebacic acid were used to block it.With flexible segment sealing was prepared.The branching degree of HBP-C was characterized by ¹³C-NMR.The results showed that the branching degree of HBP-C with n-butyric acid,n-hexanoic acid,n-octanoic acid and n-sebacic acid as capping agent was 0.36,0.83,0.86 and 0.85,respectively.It shown that the hyperbranched polyester with ideal structure has been synthesized.The laminate which modified with HBP-C of different blocking structures was characterized,when the content of HBP-C was 0 wt.%,10 wt.%,12.5 wt.%,15 wt.%,17.5 wt.%,20 wt.%was 0 wt.%,10 wt.%,17.5 wt.%.The effects of HBP-C on the mechanical properties,dielectric properties,insulation properties and anti-flaming of laminates were investigated.The results shown that when the content of flexible chain blocking hyperbranched polyester was appropriate,the dielectric constant and dielectric loss factor of laminates at 10⁷ Hz could be effectively reduced,and the insulation and mechanical properties of laminates could be improved.Improve the flame retardant properties of laminates.When the content of hyperbranched polyester blocking by n-caproic acid?HBP-C6?was15 wt.%,the cured compound has the best dielectric property at the frequency of10⁷ Hz,and the dielectric constant was 4.09 and the loss factor was 0.0056.When the content of hyperbranched polyester blocking by n-butyric acid?HBP-C4?was15 wt.%,the mechanical properties of laminates were optimal,and the bending strength of laminates reaches 557 MPa.The maximum breakdown field strength appeared in the laminate modified by hyperbranched polyester blocking by n-capric acid?HBP-C10?,and when the content was 17.5 wt.%,the value of the breakdown field strength was 30.6 kV/mm.The flame retardant grade of the HBP-C modified laminate could reach V-0.Comprehending comparison,when the content of hyperbranched polyester with n-hexanoic acid as capping agent was 15 wt.%,the comprehensive properties of laminates are optimal.And the dielectric constant,the dielectric loss factor,the bending strength,the bending modulus,the breakdown field strength,the volume resistivity and the anti-flaming were 4.09,0.0056,528 MPa,12.7 GPa,28.79 kV/mm,2.69×10¹⁴?·m and 6.4 s,respectively.