162 subjects who had been exposed to isocyanates, who had developed symptoms during the exposure period, or in the evening or night and, therefore, had a history compatible with isocyanate-induced asthma, were studied with inhalation challenge testing to isocyanates (toluene diisocyanate and methylene diphenyl diisocyanate) and methacholine, because they were suspected of having occupational as...

Diisocyanates are the most common cause of occupational asthma, but risk factors are not well defined. A case-control study was conducted to investigate whether genetic variants in inflammatory response genes (TNFα, IL1α, IL1β, IL1RN, IL10, TGFB1, ADAM33, ALOX-5, PTGS1, PTGS2 and NAG-1/GDF15) are associated with increased susceptibility to diisocyanate asthma (DA). These genes were selected bas...

Magnetorheological elastomers (MREs) are mainly composed of magnetizable particles and elastic polymer. The polymer matrix plays an important role in mechanical performances of MREs. In this study, the polyurethane (PU), which is synthesized by using toluene diisocyanate (TDI) and poly (propylene glycol) (PPG-220), is selected as a matrix because it has better degradation stability than natural...

Although relatively resistant to oxidation, polycarbonate-based polyurethanes (PCNUs) are degraded by monocyte-derived macrophages (MDM) by a co-mediated mechanism involving both hydrolytic and oxidative pathways. Since a previous study showed that PCNU pretreatment with H(2)O(2) modulated degradation by esterases, human MDM were used to further elucidate this dual pathway mechanism of degradat...

Shape memory behavior of crystalline shape memory polyurethane (SPU) reinforced with graphene, which utilizes melting temperature as a shape recovery temperature, was examined with various external actuating stimuli such as direct heating, resistive heating, and infrared (IR) heating. Compatibility of graphene with crystalline SPU was adjusted by altering the structure of the hard segment of th...

In this study, a simple and versatile synthetic approach was developed to prepare bactericidal polyurethane coatings. For this purpose, introduction of both quaternary ammonium salts (QASs), with well-known antibacterial activity, and reactive hydroxyl groups on to the backbone of soybean oil was considered. Epoxidized soybean oil was reacted with diethylamine and the intermediate tertiary amin...