PHASE-DIAGRAMS FOR BINARY POLYMER SYSTEMS EXHIBITING BOTH CRYSTALLIZATION AND LIMITED LIQUID LIQUID MISCIBILITY
PHASE-DIAGRAMS FOR BINARY POLYMER SYSTEMS EXHIBITING BOTH CRYSTALLIZATION AND LIMITED LIQUID LIQUID MISCIBILITY
复制标题
DOI：
10.1021/ma00195a082
复制
发表时间：
1989-05-01
期刊：
影响因子：
5.5
通讯作者：
BURGHARDT, WR
中科院分区：
文献类型：
--
作者：
BURGHARDT, WR
使用弗洛里-哈金斯溶液热力学计算了具有结晶度和有限液-液混溶性的二元聚合物溶液和共混物的平衡相图。结晶和液体分层的相互作用导致偏晶相结构。计算出的聚合物溶液相图与已发表的实验观察结果非常吻合，例如尽管溶剂质量变化很大，但晶体熔化曲线的小幅变化。混合曲线自由能的考虑表明，即使相图中不存在液-液平衡，液-液相分离也可能在确定晶体形态方面发挥作用。包含偏晶相和共晶相结构的相图可以由聚合物在高熔点不良溶剂中的溶液产生。计算出的不混溶二元共混物的相图表明，在大部分组成范围内，熔点降低可以忽略不计。
Equilibrium phase diagrams have been calculated for binary polymer solutions and blends exhibiting both crystallinity and limited liquid-liquid miscibility, using Flory-Huggins solution thermodynamics. The interaction of crystallization and liquid demixing results in a monotectic phase structure. Phase diagrams calculated for polymer solutions agree well with published experimental observations, such as small shifts in the crystal melting curve despite large variations in the solvent quality. Consideration of thefree energy of mixing curve indicates that liquid-liquid phase separation mayplay a role in determining crystal morphology, even when there is no liquid-liquid equilibriumin the phase diagram. A phase diagram incorporating both monotectic and eutectic phase structures may result from a solution of polymer in a high-melting poor solvent. Phase diagrams calculatedfor immiscible binary blends indicate only negligible melting point depression over most of the composition range.