Structurally organized solutions containing monomers in an ethylene glycol (EG) medium were formed and polymerized to produce polymeric solids with various morphologies, and also unique thermal and mechanical properties. Previous research had demonstrated the formation of microemulsions in an aqueous medium containing methyl methacrylate (MMA) and acrylic acid (AA). However, the non-aqueous mixtures of MMA and AA with EG did not yield conventional microemulsions. Molecularly dispersed solutions were formed in the bulk of the phase diagram, while compositions closer to the demixing line exhibited critical behaviour. This paper presents the first account of the use of mixtures exhibiting critical behaviour to produce microstructured polymers. The non-aqueous mixtures did not form any well defined microstructures on polymerization for compositions away from the two-phase boundary. Compositions exhibiting critical behaviour yielded open cell structures and also beaded polymers at high EG contents. This suggests that the microstructure in these mixtures is preserved in the final polymer to a considerable extent. The virgin polymers containing EG had very low glass transition temperatures due to the plasticizing nature of EC. The plasticizing nature of EG was also evidenced in the tensile properties of the virgin polymers
Посилання на статтю:
Microstructured polymers via photopolymerization of non-aqueous organized solutions / M. Sasthav*, W. R. Palani Raj$ and H. M. Cheung // Polymer. – 1994. – Vol 35. – P. 4072-4078.