ISSN:
0025-116X
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
The compatibility of poly(butyl acrylate) (PBA) with chlorinated polyethylene (CPE) was studied using dynamic mechanical measurements and light scattering turbidimetry. For around 50 wt.-% and above chlorination of CPE they were found to be miscible and show a lower critical solution temperature upon heating. It was found that a favourable heat of mixing of oligomeric analogues could not be taken as a guarantee of the compatibility of the corresponding polymers: the heat of mixing of PBA with cereclor 45 (chlorinated paraffin, 45, 7 wt.-% CI) is negative, but the corresponding polymers PBA/CPE3 (48,0 wt.-% CI) are immiscible. When the Flory equation of state theory is applied to the system, a large negative interaction entropy parameter Q12 must be introduced to counterbalance the large negative interaction energy parameter X12, obtained from the heats of mixing of PBA with cereclor. The simulated spinodals are flat-bottomed. However, if a much smaller negative X12 is adopted, the spinodal calculated will have more curvature. Kinetic constraints on the migration of molecules during phase separation were observed when the molecular weight exceeded certain limits and this could affect the observed cloud point diagram.
Zusätzliches Material:
7 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/macp.1983.021840712
