Sebacic anhydride

An example is poly(bis(p-carboxyphenoxy)propane) (PCPP) which has been prepared as a copolymer with various levels of sebacic anhydride (SA). Injection molded samples of poly (anhydride) / dmg mixtures display 2ero-order kinetics in both polymer erosion and dmg release. Degradation of these polymers simply releases the dicarboxyhc acid monomers (54). Preliminary toxicological evaluations showed that the polymers and degradation products had acceptable biocompatibiUty and did not exhibit cytotoxicity or mutagenicity (55). 

Sanders et al. (1999) attempted to lower the melting points of aromatic polyanhydrides by substituting branched alkyl groups in place of the linear alkyls of P(CPP-SA). They synthesized poly[l,2-bis(/ -carboxyphenoxy)-propane-co-sebacic acid] (P(1,2-CPP-SA)), poly[l,3-bis(/ -carboxyphenoxy)-2-methyl propane-co-sebacic anhydride] (P(CPMP-SA)), and poly[l,3-bis (/ -carboxyphenoxy)-2,2-dimethyl propane-co-sebacic anhydride] (P(CPDP SA)), all of which had melting points below 165°C. 

Thanos CG, Liu Z, Reineke J, Edwards E, Mathiowitz E. Improving relative bioavailability of dicumarol by reducing particle size and adding the adhesive poly(fumaric-co-sebacic) anhydride. Pharm Res 2003 20(7) 1093-1100. 

Copolymerization offers considerable potential of engineering the properties and degradation rate of PHB over a broad range. HB has been copolymerized with a number of related species, e.g., e-CL, LA, 4-hydroxybutyrate and hydrox-ypropionate. Furthermore, a number of PHB blends have been prepared. Miscibility of PHB with PCL, PLA, POE, poly(mandelic acid), and poly(sebacic anhydride) has been demonstrated. PHB-poly(sebacic anhydride) blends offered controlled release of bupivacaine at a rate dependent on the PHB content [141]. Blending of P(HB-co-HV) with natural polysaccharides was proposed as a way... 

FIGURE 6 Cross-sectional view of severalTDSs (a) poly(sebacic anhydride) (PSA) matrix device (b) membrane-moderated TDS (c) adhesive-controlled TDS (d) microreservoir-type TDS (e) matrix dispersion-type TDS. 

Chickering, D.E. Jacob, J.S. Desai, T.A. Harrison, M. Harris, W.P. Morrell, C.N. Chaturvedi, P. Mathiowitz, E. Bioadhesive microspheres HI. An in vivo transit and bioavailability study of drug-loaded alginate and poly(fumaric-co-sebacic anhydride) microspheres. J. Con-troll Release 1997, 48, 35-46. 

Aliphatic polyanhydrides H2 X = A, Adipic anhydride (AA) X = S, Sebacic anhydride (SA)... 

Chan, C.-K. Chu, I.-M. Phase behavior and miscibility in blends of poly(sebacic anhydride)/ poly (ethylene glycol). Biomaterials 2002, 23 (11), 2353-2358. 

Davies MC, Shakesheff KM, Shard AG, et al. Surface analysis of biodegreidable polymer blends of poly(sebacic anhydride) and poly(DL-lactic acid). Macromolecules 1996 29(6) 2205-2212. 

Biodegradable polymer blends of polyanhydrides and polyesters have been used as drug carriers [59], Polyflactic acid) (PLA), polyfhydroxybutyrate) (PHB), and poly(caprolactone) (PCL), of 2000 and 50000 molecular weights were mixed with poly(sebacic anhydride) (PSA), and the properties of these mixtures were studied. Mixtures of PHB and low molecular weight PLA or PCL formed uniform blends with various amounts of PSA. These blends possess different physical and mechanical properties compared to the parent polymers. The release rate of drugs from these polymeric blends increases with the increase in the content of the rapidly degrading component, PSA. 

Poly(sebacic anhydride) branched with 1,3,5 benzenetricarboxylic acid... 

In one study, the degradation of double-walled microspheres with a core of poly(l,3-bis-(p-carboxyphenoxypropane)-co-(sebacic anhydride)) 20 80 (P(CPP SA)20 80) and an external coat of poly(L-lactic acid) (PLL A) was monitored in vitro and in vivo for 6 months. The inner core of the more hydrolytically labile P(CPP SA) 20 80 degraded first, while the shell layer remained relatively intact. 

N.B. Shelke, T.M. Aminabhavi, Synthesis and characterization of novel poly (sebacic anhydride-co-Pluronic F68/F127) biopolymeric... 

Sebacic anhydride 2,2-Dimethyltrimethylene carbonate Tin-Depression Semicrystalline Wang et al. (2002a)... 

Polyanhydrides with hydrophobic fatty acid terminals have been reported (Teomim and Domb, 2001) as shown in Scheme 5.4. In this reaction, SA was polymerised with acetic anhydride to form prepolymer of poly(sebacic anhydride) (PSA). It was hydro-phobised by the interchange of polyanhydride chain with previously prepared fatty acid anhydrides of acetic acid. 

Scheme 5.4 Synthesis of nonlinear fatty acid terminated poly(sebacic anhydride).

Shakesheff, K., Davies, M., Domb, A., Jackson, D., Roberts, C., Tendler, S., Williams, P., 1995. In situ atomic force microscopy visualization of the degradation of melt-ciystallized poly (sebacic anhydride). Macromolecules 28, 1108—1114. 

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