Synthesis and properties of elastic polyurethane‐imide

Abstract

Congenital cataract, a clinically and genetically highly heterogeneous eye disorder, is one of the significant causes of visual impairment or blindness in children. It is frequently inherited as an autosomal dominant trait. We investigated a three‐generation family of Indian origin with 12 members affected with cerulean cataract. Linkage analysis was carried out in this family using more than 100 microsatellite markers for the known cataract candidate gene loci. A positive two‐point lod score of 3.9 at θ = 0.000, indicative of linkage, was obtained with three microsatellite markers for chromosome 16. Multipoint and haplotype analysis narrowed the cataract locus to a 15.3 cM region between markers D16S518 and D16S511 that corresponds to the region 16q23.1. Direct sequencing of the candidate gene MAF, which lies in the critical linked region, revealed a novel heterozygous missense mutation in the basic region (BR) of the DNA‐binding domain. This sequence change was considered pathogenic as it segregated in all affected family members, neither seen in unaffected family members nor in 106 unrelated controls. The mutation also results in substitution of highly conserved lysine 297 by arginine (K297R) that affects a residue that forms a part of a predicted DNA‐interaction region of the protein. The association of microcornea with congenital cataract in some affected individuals further underlines the role of the MAF transcription factor in lens and anterior ocular development. Our findings expand the mutation spectrum of MAF in association with congenital cataract and highlight the genetic and phenotypic heterogeneity of congenital cataract. © 2006 Wiley‐Liss, Inc.

Enhanced thermal stability and flame resistance of polyurethane‐imide foams by adding silicon carbide

“…[14,15] The soft and hard segment of polyurethane and nitrogen heterocycle of polyimide in the molecular chain backbone afford the PUI materials embracing both advantages of PU and PI. [16] Consequently, the resulting polyurethane-imide foams not only possess outstanding mechanical properties, excellent aging resistance, and soundabsorbing properties, but also show good thermal stability and structural flame-retardant properties.…”

Photoinitiator‐Free, Open‐Air Acceptor/Donor Copolymerization of Bismaleimides: Simple Polymerization Conditions for New Thermoplastic Elastomer Production

“…This property is very interesting because, for practical applications, elastomers generally need to be vulcanized with sulfur25 or reinforced by adding solid particles 26. Moreover, elastomer group possess their own advantages and drawbacks, the polyolefins are sensitive to thermal oxidation,27 polyurethane elastomers are prepared from highly toxic isocyanate,28 and the reliable fluoro‐silicon elastomers are very expensive. This novel elastomeric material can be obtained easily from UV curing which is an environmentally friendly technique, without problem of safety.…”

Bulk Preparation of Radiation Crosslinking Poly (Urethane-Imide)

“…Therefore, the preparation of radiation crosslinking poly(urethane-imide), the same need to import some unsaturated group into its molecular backbone (soft segment or hard segment ) or its chain end, to enhance adiation crosslinking effect. In fact, so far, although preparation research of poly(urethane-imide) made a lot of progress [49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67], but report closely related with radiation polymerization also not too much. Of course, we can prepare radiation crosslinking poly(urethane-imide) by using introduction of unsaturated bond into its molecular structure, especially hard segment structure, also through double end capping to prepare the radiation crosslinking poly(urethane-imide).…”

“…Radiation crosslinking via bulk polymerization is relatively simple and has the advantages of high product purity. Therefore, as a powerful means for modification of polymerric materials to be widely applied in many fields, and, radiation crosslinking modification of polyurethanes is one of most important aspects [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34].…”