Industrial Summit Technology (IST) has a fully equipped polyimide resin synthesis and development laboratory at our Parlin, NJ location. A number of new polyimide products have been developed either based on customer requests or broadly recognized industry needs. Three of these developments that will be explained further are RTM moldable polyimide, two stage curable prepreg resin, and high density foam.
The RTM moldable polyimide provides a high temperature capable resin that has the advantages of RTM molding. This processing technique eliminates the necessity of manufacturing prepreg and processing in an autoclave. An additional advantage of the RTM process is the ability to make net shape composites which is usually not possible with prepreg processing. Skybond® 8000 resin has a good balance of properties with SBS strength <12,000 psi at room temperature and good open hole compression performance 40-50,000 psi depending on fabric type and level. We have tested thermal aging performance of Skybond® 8000 with no significant property loss after 2500 hours aging at 475⁰ F.
IST’s two stage cure polyimide prepreg resin establishes the industry standard for void level in polyimide based autoclave processed composites. Void levels of less than 0.5% have been measured in composites made from both e-glass and carbon fabrics with IST’s Skybond® 800 resin system. Skybond® 800 enamel has been used to manufacture prepreg with both e-glass and carbon at resin contents of from 40-55% on standard prepreg machinery capable of coating polyimide resin systems with no manufacturing difficulties. The resulting prepreg has been processed into structural composites via autoclave to give composites with good properties and very low void levels of less than 0.5%.
The third new product that we would like to feature is our high density structural foam. With a glass temperature of 570º F the foam will have a use temperature of 525º F. The foam has excellent flame resistance with an LOI of <40 and low smoke generation level. The density of the foam can be controlled from 1 pound per cubic foot to 50 pounds per cubic foot. At the lower density the foam has excellent sound and thermal insulation properties while at high density the foam exhibits high strength for foam of over 2000 psi tensile strength. The foam can be molded to complex shapes and thus can be used to form complex shapes without need for post machining. The foam can also be supplied in a “green” state which allows the end user to mold into desired shapes. Since the foam is polyimide based it can be co-cured with polyimide skins to form sandwich structures without need for adhesives.