Structure-property relationships poly chains

The structure-property relationship of graft copolymers based on an elastomeric backbone poly(ethyl acry-late)-g-polystyrene was studied by Peiffer and Rabeony [321. The copolymer was prepared by the free radical polymerization technique and, it was found that the improvement in properties depends upon factors such as the number of grafts/chain, graft molecular weight, etc. It was shown that mutually grafted copolymers produce a variety of compatibilized ternary component blends. 

Thus, important structure/property relationships are emerging that are relevant to electronic and optical materials applications for these materials. In a different vein, side chain crystallization has resulted in the first liquid crystalline inorganic and organometallic macromolecules, viz., unusual poly(dialkoxy-phosphazenes) described by Allcock (p. 250) and Singler (p. 268). 

Here we report preliminary results on the multiple fluorescence emission of 1 and 2. From structure-property relationships, solvent effect and temperature effect studies, we are able to show that the multiple emission is from the emission of free squaraine in solution, the emission of the solute-solvent complex and the emission of a twisted relaxed excited state. Further solvent effect study using 2 as a model shows that squaraine forms strong solute-solvent complexes with alcoholic solvent molecules. Analogous complex-ation process is also detected between 1 and the hydroxy groups on the macromolecular chains of poly(vinyl formal). The Important role of this complexation process on the stabilization mechanism of particles of 1 in polymer solution is discussed. 

An investigation of poly(di- -alkylsilane)s with short side chains assumes a critical importance for a generalized understanding of the structures, energetics and phase transition of this novel class of polymers. The structures of the poly(di-n-alkylsilane) family are far more complicated than presumed to date, requiring a re-examination of our current understanding of the structure-property relationships of these important polymers. 

As a function of the comonomer incorporation, it is possible to control PE crystallization. Above 20 mol.% 1-octene content, chain folding is not possible and fringed-micelle type nanostructures are formed Basic structure/property relationships of poly(ethylene-co-l-octene) were reported by Minick et al. [12]. 

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