Molecular weight distribution has been investigated for polycaproamide obtained in lowtemperature, anionic polymerization of caprolactam in the presence of the sodium salt of caprolactam and carbon dioxide in solvent; fractionation has been performed at 25 ° using phenol-tetrachloroethane as solvent
On distribution of molecular weight in anionic polymerizates of caprolactam
✍ Scribed by Jan Roda; Jaroslav Králíček; Šanda Karel
- Publisher
- Elsevier Science
- Year
- 1976
- Tongue
- English
- Weight
- 271 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0014-3057
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✦ Synopsis
Measurement has been made of the dependence of the molecular weight distribution on the ratio of the catalytic system components and on the polymerization time for polycaprolactam obtained by anionic polymerization. A bimodal character of the curves was observed for products made using molar ratios of activator (N-benzoylcaprolactam) to initiator (sodium dihydro-bis(methoxyethoxy)aluminate) of 1:1 and 1:3, when the polymerization times were less than 1 hr. This course is explained by the influence of fast side-reactions, mainly condensations. For a ratio of 3:1 of the components of the catalytic system, smooth integral distribution curves are obtained, accounting for a very fast decrease in the strong base concentration in the initial stages of the polymerization.
📜 SIMILAR VOLUMES
A~tntct--Molecular weight of polycaproamide obtained by anionic polymerization of caprolactam in solution in the presence of sodium caprolactam and carbon dioxide has been investigated by absolute methods. Number average molecular weights were determined by osmometry. Weight average molecular weight
## Abstract The molecular weight distribution (MWD), formed during random crosslinking of polymers whose initial molecular weight distribution is given by the Schulz‐Zimm distribution, is proposed. The obtained equation can be considered as a good approximation even for nonrandom crosslinking react