Rheological Properties of the Solutions of Incompatible Polymer Blends

[摘要] A blend polymeric system composed of poly(methyl methacrylate) (PMMA or PM) and polystyrene (PS) dissolved in chloroform was rheologically studied. The viscosities ョbl of the blend system with various blending ratios �? changing from zero (pure PS solution) to unity (pure PMMA solution) were measured at 25�? as a function of shear rates s by using a Couette type viscometer. ョbl at a given s decreased exponentially with �? reaching asymptotic constant value of ョbl ; ョbl at a given �? is greater at a smaller s. These results are explained by using Ree-Erying`s theory of viscosity, ョbl = (x1�?1/�?1)bl �? (x2�?2/�?2)bl [sinh-1�?2(bl) s]/�?2(bl)s. The Gibbs activation energy ツGi× (i = 2 for non-Newtonian units) entering into the intrinsic relaxation time モi is represented by a linear combination ツGi×(bl) = ヶツG×iPM �? (1-�?)ツG×iPS;the intrinsic shear modulus[メi]-1 is also represented by [メi(bl)]-1 = ヶ[メiPM]-1 �? (1-�?)[メiPS]-1 and the fraction of area on a shear surface occupied by the ith flow units xi(bl) is similarly represented, i.e., xi(bl) = ヶxiPM �? (1-�?)xiPS. By using these ideas the Ree-Eyring equation was rewritten which explained the experimental results satisfactorily.

[学科分类] 化学（综合）