Viscometric study of polymer–polymer interactions in ternary systems—II. The influence of solvent
1998; Elsevier BV; Volume: 34; Issue: 9 Linguagem: Inglês
10.1016/s0014-3057(97)00260-7
ISSN1873-1945
AutoresYang Haiyang, Pingping Zhu, Shiqiang Wang, Zeng Yiming, Qipeng Guo,
Tópico(s)Polymer crystallization and properties
ResumoThe variation of reduced viscosity (ηsp/C) with concentration has been studied for poly(vinyl chloride) (PVC), poly(ε-caprolactone) (PCL) and mixtures of PVC/PCL with weight ratio of 1:1 in N,N′-dimethylformamide (DMF), tetrahydrofuran (THF) and mixtures of DMF/THF with different volume ratios at 25°C, respectively. Solvent is believed to play a key role in characterizing the viscosity behavior in solution. In the ternary system of PVC–PCL–DMF, there exists a positive deviation from linear relationship at low concentrations; on the contrary, in the system of PVC–PCL–THF, there is a negative deviation from linear relationship at low concentrations. As for PVC/PCL in mixed solvent of DMF/THF, the viscosity behavior is dependent on the volume ratio of DMF/THF. In case the volume ratio of DMF/THF is 10:6, a linear relationship is obtained in the plot ηsp/C vs concentration. If the volume ratio of DMF/THF is less than 10:6, a negative deviation from relationship at low concentration exists, which is similar to that of PVC/PCL in THF. On these occasions, polymer–solvent interaction is believed to be dominant over polymer–polymer interaction.
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