The adhesives industry is increasingly interested in products coming from natural and renewable resources. aim of the present work was to improve water resistance soy-based proteins by using synthetic formaldehyde-free additives. These include polyamide-amine epichlorohydrin (PAE), different types isocyanates, combinations these cross-linkers between them with other agents, including metal ions...

The photochemistry and molecular structure of 1-phenyl-4-allyl-tetrazolone (PAT) was studied by FT-IR matrix isolation spectroscopy and DFT(B3LYP)/6-311++G(d,p) calculations. The spectrum of matrix-isolated PAT monomers agrees well with the sum spectrum of three conformers predicted theoretically. UV irradiation (lambda > 235 nm) of matrix-isolated PAT induces three types of photofragmentation:...

Received: July 28, 2017 Revised: October 17, 2017 Accepted: November 02, 2017 Abstract: Background: Isocyanates are mainly considered respiratory allergens but can also cause contact allergy. Diphenylmethane-4,4′-diamine (4,4′MDA) has been considered a marker for diphenylmethane-4,4′-diisocyanate (4,4′-MDI) contact allergy. Furthermore, overrepresentation of positive patch-test reactions to p-p...

A self-assembled capsule facilitates reactions of isocyanates with water. The capsule provides an amphiphilic environment with hydrophobic aromatic ends and hydrophilic glycoluril units at the center. Reaction takes place in the narrow, cylindrical space to form the N,N-dialkylurea, which then appears in a longer capsule.

Review Isocyanates, a group of reactive chemicals [with the functional group N = C = O (NCO)] used extensively in the production of numerous polyurethane foams, coatings, and a wide array of consumer products, are a major cause of occupational asthma worldwide. The polyurethane industry has expanded dramatically , along with the number of workers and consumers at risk for exposure. Inhalation h...

OBJECTIVE To examine the quantitative relation between exposure to isocyanates and occupational asthma, and to explore the role of atopy and smoking in occurrence of the disease. METHOD A case-referent study was undertaken of cases from two manufacturing companies (A and B) from which referents without disease could be selected and reliable exposure measurements were available. In company A, ...

BACKGROUND Isocyanates are some of the leading occupational causes of respiratory disorders, predominantly asthma. Adequate exposure monitoring may recognize risk factors and help to prevent the onset or aggravation of these aliments. Though, the biomonitoring appears to be most suitable for exposure assessment, the sampling time is critical, however. In order to settle the optimal time point f...