HIGH-STRENGTH, ULTRA-THIN AND FIBER-REINFORCED PHEMA ARTIFICIAL SKIN

Membranes of pHEMA-based composites were manufactured by adding variou s kinds of weaved and knitted fabrics and fibers into a deionized wate r solution of HEMA monomer, EGDMA cross-linker and BIE initiator, and followed by polymerization under ultraviolet radiation. By varying the amount of initial water addition (IWA), the dimensional change of pHE MA matrix from the newly fabricated state to the eventually swollen st ate could be adjusted to reduce the swellability mismatch with the fab rics and the possibility of the swollen membranes becoming folded and curled was avoided. Mechanical properties of the fiber-reinforced pHEM A composites, including yielding strength, maximum strength, Young's m odulus and elongation at break, are improved evidently depending on th e mechanical characteristics of additives applied. The involvement of fabrics and fibers in the soft pHEMA matrix also provides an alternati ve of making the ultra-thin membranes to overcome the problem of easil y being torn during handling. In addition, some of these membranes als o exhibit an improvement in water transmission rate. (C) 1998 Publishe d by Elsevier Science Ltd. All rights reserved.