Laminates Aramid based

The reinforcing fabrics used were aramid (Kevlar DuPont) and poly(p-pheny-lene-2,6-benzobisoxazole) (PBO) (Zylon Toyobo). The fabrics were first treated with a 1.5% solution of HB PAMAM (AD-102), dried, then interleaved with an epoxy film structural adhesive (epoxy stage B on polyester net), and compression-molded for 90 min at 120 °C. For the aramid-based composite, FM-73 (Cy-tec) was used as the matrix. For the PBO-based composite, AF-191 (3M) was used as the matrix. The laminates were cut into strips and tested for interlaminar shear strength (ASTM D-2344) using a three-point bending instrament. 

Composites. The history of phenoHc resin composites goes back to the early development of phenoHc materials, when wood flour, minerals, and colorants were combined with phenoHc resins to produce mol ding compounds. In later appHcations, resin varnishes were developed for kraft paper and textile fabrics to make decorative and industrial laminates. Although phenoHcs have been well characterized in glass-reinforced composites, new developments continue in this area, such as new systems for Hquid-injection molding (LIM) and sheet-molding compounds (SMC). More compHcated composite systems are based on aramid and graphite fibers. 

Epoxide resins reinforced with carbon and Aramid fibres have been used in small boats, where it is claimed that products of equal stiffness and more useable space may be produced with a 40% saving in weight over traditional polyester/ glass fibre composites. Aramid fibre-reinforced epoxide resins have been developed in the United States to replace steel helmets for military purposes. Printed circuit board bases also provide a substantial outlet for epoxide resins. One recent survey indicates that over one-quarter of epoxide resin production in Western Europe is used for this application. The laminates also find some use in chermical engineering plant and in tooling. 

Towflex (Hexcel Composites) is based on carbon, glass or aramid fibres impregnated with polypropylene, polyamide, PPS, polyetherimide, PEEK. Product forms include flexible Towpreg, woven fabric, braided sleeving, UD tape, chopped compression moulding compound, moulded plates, thermoformable laminates. 

Tepex (Bond-Laminates) is delivered as sheets of 0.25-3 mm thickness based on carbon, glass or aramid fibres impregnated with polyamide or thermoplastic polyester. Fibre levels range from 35% up to 85%. 

In 2007 Sumitomo Chemical announced plans to expand production of its lithium ion secondary battery separator Pervio in stages (mid-2008 12 million m /year, end 2008 16 million m /year, mid-2009 25 million m /year). The Pervio separator is made by laminating a polyolefin base material and an aramid heat-resistant layer to provide exceptional heat resistance. Sumitomo Chemical was the first company to commercialize a product with this aramid heat-resistant layer technology. 

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