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Schneider, J. E.

Publications and source records attributed to Schneider, J. E..

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Toxicity of pyrolysis gases from polytetrafluoroethylene

A sample of polytetrafluoroethylene was evaluated for toxicity of pyrolysis gases, using various test conditions of the toxicity screening test method developed at the University of San Francisco. Time to death appears to be affected by the material of which the pyrolysis tube is made, with Monel tending to give longer times to death than quartz. When quartz tubes are used, time to death seems to be related to carbon monoxide concentration. When Monel tubes are used, carbon monoxide does not appear to be the principal toxicant.

Hilado, C. J.↗
NASA NTRS1979

Toxicity of pyrolysis gases from polypropylene

A sample of polypropylene was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. The gases from this sample appeared to be equivalent or less toxic than the gases from a sample of polyethylene under these particular test conditions. Carbon monoxide appeared to be the principal toxicant.

Hilado, C. J.↗
NASA NTRS1979

Toxicity of pyrolysis gases from polyoxymethylene

A sample of polyoxymethylene was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. Under several test conditions, this material gave shorter times to death than many other synthetic polymers. Carbon monoxide appeared to be the principal toxicant in the pyrolysis gases.

Hilado, C. J.↗
NASA NTRS1978

ALC/50/ values for some polymeric materials

Apparent lethal concentrations for 50 per cent of the test animals within a 30-min exposure period (ALC/50/) were determined for seventeen samples of polymeric materials, using the screening test method. The materials evaluated included resin-glass composites, film composites, and miscellaneous resins. ALC(50) values, based on weight of original sample charged, ranged from 24 to 110 mg/l. Modified phenolic resins seemed to exhibit less toxicity than the baseline epoxy resins. Among the film composites evaluated, only flame modified polyvinyl fluoride appeared to exhibit less toxicity than the baseline polyvinyl fluoride film.

Hilado, C. J.↗
NASA NTRS1977

Toxicity studies of a polyurethane rigid foam

Relative toxicity tests were performed on a polyurethane foam containing a trimethylopropane-based polyol and an organophosphate flame retardant. The routine screening procedure involved the exposure of four Swiss albino male mice in a 4.2 liter hemispherical chamber to the products generated by pyrolyzing a 1.00 g sample at a heating rate of 40 deg C/min from 200 to 800 C in the absence of air flow. In addition to the routine screening, experiments were performed with a very rapid rise to 800 C, with nominal 16 and 48 ml/sec air flow and with varying sample rates. No unusual toxicity was observed with either gradual or rapid pyrolysis to 800 C. Convulsions and seizures similar to those previously reported were observed when the materials were essentially flash pyrolyzed at 800 C in the presence of air flow, and the toxicity appeared unusual because of low sample weights required to produce death.

Hilado, C. J.↗