نتایج جستجو برای: 4 diisocyanate
تعداد نتایج: 1304649 فیلتر نتایج به سال:
toluene diisocyanate (tdi) is an imperative chemical substance used in the production of polyurethane foams, elastomers, paints and coatings that cause a variety of health problems in workers who are exposed in work places. this study aimed to determine the asthma symptoms and serum specific ige levels in tdi exposed workers and comparing the results with healthy control group.all the plants th...
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...
Bayer, Rinke, Siefken, Orthner, and Schild in 1937 and 1942 demonstrated the possibility of producing high molecular compounds with extraordinary chemical and physical properties by means of a so-called diisocyanate-polyaddition procedure. The basic reaction, leading to low-molecular products, had been known for about 100 years. Bayer and his colleagues were able to show, however, that the reac...
Segmented linear polyurethanes (PUs) containing Diels-Alder (DA) adduct were synthesized in toluene solution from poly("-caprolactone) (PCL, Mn = 10, 25 and 50 kg/mol), diisocyanate (methylene diphenyl diisocyanate (MDI), 2,4toluene diisocyanate (TDI), 1,6-hexamethylenediisocyanate, (HDI)), furfurylamine (FA) and bismaleimide (BMI). The order of the segments in the PUs was -PCL-MDI-FA-BMI-. The...
Implant infections remain a major healthcare problem due to the prolonged hospitalisation period required to disrupt and treat bacterial biofilm formation, and the need for additional surgery to remove/replace the infected implant, which if not removed in a timely manner may lead to sepsis. Although localised drug administration, via an implanted scaffold, has shown promise in a clinical settin...
OBJECTIVES 1,5-Naphthalene diisocyanate (NDI) is used in the plastic industry as a curing agent. 1,5-Naphthalene diisocyanate is classified as a sensitizing agent. The objective of this study has been to develop biomonitoring methods for the evaluation of exposure to NDI. MATERIAL AND METHODS We obtained blood and urine samples from a group of 20 male workers exposed to NDI. The workers answe...
The determination of isocyanates concentrations in air is complicated by thepresence of these substances as monomers and oligomers as well as in thevapor and aerosol phases. Direct-reading instruments (DRIs) are available fordetermining the diisocyanate concentrations in workplace air, but they arecalibrated for the monomers only. Industry uses polymeric diisocyanateswhich c...
This study reports the fabrication and performance of sustainable polyurethane (PU) films based on wheat starch (native NS, modified MS), bio-polyols (1,3-propanediol PD, glycerol Gly), polymeric diphenylmethane diisocyanate (pMDI). NS was successfully with isophorone diisocyanate, confirmed by Fourier transform infrared spectroscopy (FTIR) 13C nuclear magnetic resonance (13C NMR). Various PU w...
There is virtually no information in the literature about the exposure levels needed to induce hypersensitivity pneumonitis (HP) by diisocyanates. The present study reports a case of occupational HP due to diisocyanates after low-level exposure. A 53-yr-old female never-smoker developed progressive shortness of breath on exertion, cough, fatigue and flu-like symptoms shortly after she began wor...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید