A series of copolymers of 4'-[[[2-(methacryloyloxy)ethyl]ethyl]amino]-4-nitroazobenzene (DR1M) and an optically "inert" styrene comonomer were tested for photoinduced birefringence. The level of saturated birefringence increased linearly with the content of DR1M in the copolymer. The birefringence per mole of azo chromophore was constant along the copolymer series.Key words: azobenzene, photoinduced birefringence, copolymers, trans-cis isomerization.

Two new classes of highly unsaturated polymers—polyethynylpolyarenes and polyazopolyarenes are synthesized by oxidative polycondensation of polyethynylarenes in the first case and of aromatic diamines in the second one and investigated. The polymers have common formulas H[(CC)kAr(CC)k]nH and H2NArN(NArN)NArNH2 respectively. The polymers either keep the conjugation along the main chain or the conjugation is intentionally broken. This is attained by changing the structure of the arylenic part of the monomers. Depending on the structure, electrical properties of the polymers vary in a wide range. For example the conductivity at 20°C. varies from 10−2 to 10−20 ω−1 cm.−1. The temperature dependence of conductivity is σ = σ0 exp {−E/kT}. The activation energy is specially predetermined by the structure and can vary in the range of 0.1 to 4.7 e.v. Similarly magnetic, dielectric, catalytic and other properties and solubility can be changed by varying the structure.

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A resuscitative compound in freeze-dried form has been synthesized between a modified starch and a tetremerically stabilized hemoglobin. In order to complex the hemoglobin, the starch has been prepared in mono-, di-, tri-, and tetra-aldehyde moieties. The hemoglobin was stabilized with low molecular weight diacids. Electrophoretic densitometric patterns indicate compound formation. The resulting polymers were characterized with respect to oxygen transport (biotonometry), Hill constant and P50. The in vivo evaluation indicates that these compounds are effective in exchange-transfusion experiments with rats to a level of about 85% replacement of whole blood. The final product is a cost-effective acellular resuscitative compound which can be stored in freeze-dried form at room temperature for extended periods of time. This artificial blood substitute can be reconstituted upon the addition of water.

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