Dielectric properties and their dependence of polyetherimide/bismaleimide blends for high performance copper clad laminates

Mechanical and thermal properties of a novel bismaleimide matrix resin for high-performance composite materials

A novel bismaleimide matrix resin of amino-polythioetherimide (PTEI-N)/4,4′-bismaleimidodiphenyl methane (BDM)/2,2′-diallylbisphenol A (BA) was prepared. Mechanical measurements, dynamic thermomechanical analysis, thermogravimetric analysis (TGA), and microanalyses were conducted to assess the mechanical properties, thermal resistance, and morphology of the modified resin. Results demonstrate that the addition of PTEI-N has significant effects on the mechanical properties of the BDM/BA system. Compared with the pure BDM/BA resin, the PTEI-N/BDM/BA system markedly improves the tensile strength, flexural strength, and impact strength, given an appropriate amount of PTEI-N. Scanning electron microscopic and energy-dispersive spectroscopic results show that PTEI-N is distributed uniformly in the BDM/BA system, and the interfacial compatibility between the PTEI-N and BDM/BA phase is excellent. TGA shows that the BDM/BA resin continues to exhibit good thermal resistance with a suitable dosage of PTEI-N. These changes in properties are closely correlated with the addition of PTEI-N. The PTEI-N/BDM/BA resin system shows potential applications in many fields.

Thermally Stable Siloxane Hybrid Matrix with Low Dielectric Loss for Copper-Clad Laminates for High-Frequency Applications

We report vinyl-phenyl siloxane hybrid material (VPH) that can be used as a matrix for copper-clad laminates (CCLs) for high-frequency applications. The CCLs, with a VPH matrix fabricated via radical polymerization of resin blend consisting of sol-gel-derived linear vinyl oligosiloxane and bulky siloxane monomer, phenyltris(trimethylsiloxy)silane, achieve low dielectric constant (Dk) and dissipation factor (Df). The CCLs with the VPH matrix exhibit excellent dielectric performance (Dk = 2.75, Df = 0.0015 at 1 GHz) with stability in wide frequency range (1 MHz to 10 GHz) and at high temperature (up to 275 °C). Also, the VPH shows good flame resistance without any additives. These results suggest the potential of the VPH for use in high-speed IC boards.

Preparation and characterization of a novel composite of polythioetherimide/bismaleimide/2,2′-diallylbisphenol A

A novel composite of polythioetherimide (PTEI)/bismaleimide (BMI)/2,2′-diallylbisphenol A (BA) was prepared. Mechanical measurements, dynamic thermomechanical analysis, and microanalysis were conducted to assess the toughness and morphology of the composite. Results demonstrate that the addition of PTEI has significant effects on the mechanical properties of the BMI/BA system. Compared with the BMI/BA resin, the PTEI/BMI/BA system significantly improves the impact strength and bending strength, given an appropriate amount of PTEI. Scanning electron microscope (SEM) images and energy dispersive spectroscopy results show that PTEI is distributed uniformly in the PTEI/BMI/BA system and that the interfacial compatibility between the PTEI and BMI/BA phase is excellent. Thermogravimetric and dielectric analyses were also conducted to infer the thermal and dielectric properties of the composite. With a suitable addition of PTEI, the BMI/BA resin still exhibits good thermal resistance and dielectric constant and loss values of the blends still retain good stability in a frequency band from 10 MHz to 60 MHz. All these changes in properties are closely correlated with the addition of PTEI.