A kind of aromatic diamine

4'

4-(2

2-diphenylethene-1

1-diyl)dibiphenyl-4-amine (TPEDA) containing nonplanar rigid twisted moieties in the molecular structure was used as curing agent to prepare epoxy resins cured composites with commercial epoxy resins (E51).Comparing with conventional diamines (4

4'-diaminodiphenylmethane

DDM and 4

4'-diaminodiphenylsulfone

DDS)

the properties of system E51/TPEDA

such as glass transition temperature

elastic modulus

stress relaxation and creep

thermal expansion

the dielectric constant and dielectric loss

were roundly studied by dynamic mechanic analysis (DMA)

thermal mechanic analysis (TMA)

impedance analyzer

et al.The results show that the structure of rigid non-specific coplanar diamine TPEDA as epoxy curing agent

can significantly improve the glass transition temperature (258 ℃)

elastic modulus (23.7 MPa) and dimensional stability

while reduce the thermal expansion coefficient of the cured product (CTE1:61.9612 10-6

CTE2:138.3265 10-6)

dielectric constant (4.76 at 1 kHz) and the dielectric loss (1.93 10-2 at 1 MHz).When TPEDA which contains a special twisted steric structure is introduced into the epoxy resin main chain

it minimizes the strong interaction and tight stacking of the molecular chains and then increases the free volume of the polymers.Furthermore

the abundant rigid moieties in TPEDA used as curing agent can also improve the thermal stability of epoxy resins.Therefore E51/TPEDA can be used for high-density integrated circuit device package.