Phase behavior in copolymer blends of polystyrene and poly(o-chlorostyrene-co-p-chlorostyrene)

Abstract

The miscibility of random copolymers of o-chlorostyrene and p-chlorostyrene [P(oClS-pClS)] with polystyrene (PS) has been studied by differential scanning calorimetry (DSC). A miscibility ‘‘window’’ was found, extending in copolymer composition from about 68 to 98 mole % o-chlorostyrene at a temperature of 150 °C. The maximum in the miscibility window occurred at approximately 170 °C and a composition of 83 mole % o-chlorostyrene. This result differs only slightly from theoretical predictions based on interaction parameters previously calculated from miscibility behavior in blends of poly(2,6-dimethyl-1,4-phenylene oxide) with P(oClS-pClS), poly(styrene-co-o-chlorostyrene) and poly(styrene-co-p-chlorostyrene). The implication of this result for the numerical values of the six interaction parameters required to describe these blends is discussed.

Interaction between poly(vinyl pyridine) and poly(2,6-dimethyl-1,4-phenylene oxide): A copolymer blend miscibility study

“…P(S-co-2VP), since c S;PPO , c S;4VP and c S;2VP are already known from the literature. For the former a value of c S;PPO ¼ À0:043 is taken [32,44]. It should, however, be realized that this is only an approximate value and that the real value will, moreover, be temperature dependent.…”

Phase behavior of blends of poly(2,6-dimethyl-1,4-phenylene oxide)/polystyrene/poly(o-chlorostyrene-co-p-chlorostyrene) copolymer

“…In the present case the binary 1-2 interaction parameter can be calculated from Eq. (1) and the available data: x S=o-ClS ¼ 0:005 [15], x S=pClS ¼ 0:0792 [18], and x o-ClS=p-ClS ¼ 0:16 [14] to yield x S=cop ; x 12 ¼ 0:0021: Fig. 1 shows that this value yields a very good fit to the experimental data.…”

“…The two homopolymers are known to be miscible for all molecular weights and experimentally accessible temperatures and therefore (with one exception, [25]) all published values for x S=PO are negative, ranging from 2 0.986 to 2 0.021; some of this variation may be due to temperature effects. There is also some variability in the published values [14,15,29] for the other five x ij relevant to this system but the uncertainty is far lower than is the case for x S=PO :…”

“…The parameter x PO=cop can be calculated from Eq. (1) and the available data x PO=o-ClS ¼ 0:02 [15], x PO=pClS ¼ 0:03 [15], and x o-ClS=p-ClS ¼ 0:16 [15] and is equal to 2 0.015. This value for x S=PO therefore lies slightly below the range of previously published value for this parameter.…”

“…In the present study, the binary interactions of the copolymer x i=cop ; where i ¼ PS, PPO, with the two respective homopolymers can be treated according to the established methods [14,15]. Thus,…”