JOM KITA KE POLITEKNIK

Thermal Degradation of Fractionated High and Low Molecular Weight Polystyrenes (Record no. 84)

MARC details
042 ## - AUTHENTICATION CODE
Authentication code dc
100 10 - MAIN ENTRY--PERSONAL NAME
Personal name Madorsky, S. L.
Relator term author
9 (RLIN) 217
245 00 - TITLE STATEMENT
Title Thermal Degradation of Fractionated High and Low Molecular Weight Polystyrenes
260 ## - PUBLICATION, DISTRIBUTION, ETC.
Name of publisher, distributor, etc. [Gaithersburg, MD] : U.S. Dept. of Commerce, National Institute of Standards and Technology,
Date of publication, distribution, etc. 1962.
500 ## - GENERAL NOTE
General note /pmc/articles/PMC5312812/
520 ## - SUMMARY, ETC.
Summary, etc. In previous work on the thermal degradation of polystyrene of average molecular weight of 230,000, carried out in a vacuum in the temperature range 318 to 348 °C, the rate curves exhibited distinct maximums when percentage loss of sample per minute was plotted as a function of percentage volatilization. These maximums correspond to a volatilization of about 35 to 45 percent and tend to flatten with decreased temperature of pyrolysis. A similar study of rates of thermal degradation at 307.5 °C has now been made on two groups of polymers: (1) low molecular weight, 24,000; 51,000; and 66,000; and (2) high molecular weight, 2,000,000; 2,250,000; and 5,000,000. Whole polymers and also fractions of narrow-range molecular weight were used. The rate curves for the 24,000 and 51,000 molecular-weight samples exhibit very high initial rates, but no maximums; the 66,000 sample showed a maximum at 45 percent volatilization. The rate curves for the 2,000,000, 2,250,000, and 5,000,000 molecular-weight samples exhibit a gradual rise up to about 25 percent volatilization; then, instead of forming maximums, they follow plateaus to about 50 percent volatilization. These plateaus are indicative of a zero-order reaction in the range that they cover, and the rates corresponding to them fit well on the Arrhenius activation-energy curve obtained previously for polystyrene samples at higher temperatures.
540 ## - TERMS GOVERNING USE AND REPRODUCTION NOTE
Terms governing use and reproduction
540 ## - TERMS GOVERNING USE AND REPRODUCTION NOTE
Terms governing use and reproduction https://creativecommons.org/publicdomain/zero/1.0/
540 ## - TERMS GOVERNING USE AND REPRODUCTION NOTE
Terms governing use and reproduction The Journal of Research of the National Bureau of Standards Section A is a publication of the U.S. Government. The papers are in the public domain and are not subject to copyright in the United States. Articles from J Res may contain photographs or illustrations copyrighted by other commercial organizations or individuals that may not be used without obtaining prior approval from the holder of the copyright.
546 ## - LANGUAGE NOTE
Language note en
690 ## - LOCAL SUBJECT ADDED ENTRY--TOPICAL TERM (OCLC, RLIN)
Topical term or geographic name as entry element Article
9 (RLIN) 221
655 7# - INDEX TERM--GENRE/FORM
Genre/form data or focus term Text
Source of term local
9 (RLIN) 222
700 10 - ADDED ENTRY--PERSONAL NAME
Personal name Mclntyre, D.
Relator term author
9 (RLIN) 218
700 10 - ADDED ENTRY--PERSONAL NAME
Personal name O'Mara, J. H.
Relator term author
9 (RLIN) 219
700 10 - ADDED ENTRY--PERSONAL NAME
Personal name Straus, S.
Relator term author
9 (RLIN) 220
786 0# - DATA SOURCE ENTRY
Note J Res Natl Bur Stand A Phys Chem
856 41 - ELECTRONIC LOCATION AND ACCESS
Uniform Resource Identifier <a href="http://dx.doi.org/10.6028/jres.066A.029">http://dx.doi.org/10.6028/jres.066A.029</a>
Public note Connect to this object online.

No items available.