Patent · US Expired

Polybutadiene and polyisoprene thermosetting compositions and method of manufacture thereof

US5972811A · kind A · utility

16Cited by
23References
42Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 4, 1998
Grant dateOct 26, 1999
Priority date
Expiry dateJun 4, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T442/3455
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

An electrical substrate material is presented comprising a thermosetting matrix of polybutadiene or polyisoprene and a co-curable second resin distinct from the first resin. A peroxide cure initiator and/or crosslinking agent may optionally be added. The presence of a very high surface area particulate filler, preferably fumed silica, is also preferred, in that its presence results in a prepreg which has very little tackiness and can therefore be easily handled by operators. This low tackiness feature allows for the use of conventional automated layup processing, including foil cladding, using one or more known roll laminators. While the prepreg of this invention is tack-free enough to be handled relatively easily by hand, it is also tacky enough to be tacked to itself using a roll laminator (e.g., nip roller) at room temperature. The composition of this invention is particularly well suited for making electrical circuit substrates for microwave and digital circuits, typically in the form of the thermosetting composition being laminated onto one or both opposed surfaces to a metal conductive foil such as copper.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.