ISSN:
0032-3888
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Intramolecular reactions in the step-growth polymerization of multifunctional monomer, RAf, were modeled. The rate constant for this step was taken from the Monte Carlo studies of Plate and Noah. Species Pvn, with v Intramolecular bonds and chain length n, was defined, and differential equations governing their molecular weight distribution (MWD) in hatch reactors were written. An algorithm of computation valid up to the gel point was developed, and the process of gelation was studied under the variation of the rate constant parameters of the intramolecular reaction step. It was found that the larger the molecule, the greater is its tendency to form intramolecular bonds. We devised a mathematical method to find the conversion of A groups on Pon species. Whenever this reaches a critical value {= l/(f-1)}, conditions for gelation are generated and molecules of infinite structure begin to form. In the presence of intramolecular reactions, the tendency to form a network is reduced because larger molecules undergo cyclization and there is consequently a shift in the gel point, which has been computed in this work.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pen.760280108
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