Poly polarized light microscope

We have recently initiated our investigation of blends by examining the compatibility between our modified polymer sample 4 and poly(methyl methacrylate). Mixtures with a composition of between 10% and 30% of sample 4 yield compatible blends which are transparent under a polarized light microscope, and are characterized by a single Tg. Mixtures richer than 60% of 4 undergo complete phase separation. 

Compatibility of two- and threecomponent systems of poly(vinyl chloride) with homo- and copolymers of methyl methacrylate and butyl methacrylate has been studied. The mixtures were tested for compatibility in the dynamic viscosity of polymer solutions, in microscopic observations in polarized light, as well as by dynamic mechanical measurements. It was found that poly(methyl methacrylate) and methacrylic copolymers were compatible with PVC. Poly(butyl methacrylate) appears to be incompatible with PVC. Estimation of solubility parameter values 6 made it possible to predict the compatibility of polymer pairs. Critical A6 value for compatible polymers has been found to be 0.5 (cal cm 3)1/2. 

Poly(N-(p-cyanobenzylidene)-p-aminostyrene), (PCBAS). Polymerization of the monomer from the nematic and isotropic states proceeds over a few hour period (10). Samples polymerized at 127 C for 24 hours show a very weak diffuse inner ring at 29 4.2 degrees. This is much less intense than expected from comparisons with low molecular weight nematics. Within the outer halo there is a sharp line corresponding to 4.43. Films of the polymer are transparent, but are weakly birefringent. Light of low intensity is transmitted between crossed polarizers in the optical microscope. 

The polarizing microscope requires a linear polarizer between the light source and the sample and an analyzer - another linear polarizer - after the sample. They should be rotatable. The polarizers used presently work by absorbing light of one polarization state and allowing the other to pass that is, they are dichroic filters. The material used is a Polaroid sheet, a highly oriented film of doped poly(vinyl alcohol). Other features desirable in a polarizing microscope are as follows ... 

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