Polymer azopolymer

Large intestine 1.5 4-16 5.5-7 Contains specific enzymes that may be exploited for drug release. Polymers that are specifically degraded by such enzymes include saccharide-containing polymers or azopolymers... 

In an effort to develop a peroral application system for insulin, Saffran was the first to use azopolymers as protective colon delivery coating, by use of the aforementioned strategy of azo-linked prodrugs [58, 59], Originally, he used azo-linked copolymers of styrene and hydroxyethylmethacrylate to coat and protect the insulin. However, this approach is not restricted to hydroxyethylmethacrylate and can indeed be accomplished in the same way by an almost unlimited number of similar polymer types. 

Side reactions in the oxidative coupling of primary aromatic diamines to azopolymers could severely limit the molecular weights of polymers obtainable and disrupt their ordered, linear structure. To investigate this point the following polymer... 

Color. All aromatic azopolymers are colored owing to the strongly chromophoric azogroup. Even the azoblock copolymer derived from a phenyl oxide-isophthalamide backbone (discussed earlier) which has only one azogroup per repeat unit of a molecular weight of 3500 is bright yellow. Naturally, the shade of color of individual polymers depends on the structure of the repeat unit as expected, fully conjugated polymers... 

Fiber Properties. One of the polymers, the poly(isophthalamide) of 4,4 -diaminoazobenzene (IV), was selected for investigation of fiber properties of aromatic azopolymers. Table III shows standard tensile data of the "as spun as well as the hot-drawn (1.5X, 350°C.) fiber. As shown, this polymer has tensile properties fairly typical of an aromatic polyamide. 

Mass transport associated with photodegraded azochromophores, which occurs for high-power writing lasers. It has been observed with azopolymers as well as small dyes transferred onto a polymer film by the ELBL technique. It is interesting that, for spin-coated high Tg polymer... 

In SRGs inscribed on LC polymer films, time evolution has also been reported in reference 13. TTie depth of the SRG was seen to increase from 70 nm up to 300 nm, 16 h after the writing process was completed. During this period, the samples were left to rest under dark conditions. Ozaki et also showed that the SRG formation processes even after terminating the laser light irradiation on a composite film of an azopolymer and a conducting polymer derived from poly(p-phenylene vinylene). 

Xripathy, S. K., Viswanathan, N. K., Balasubramanian, S., and Kumar, J. Holographic fabrication of polarization selective diffractive optical elements on azopolymer film. Polym. Adv. Technol. 2000,11, pp. 1-5. 

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