Sebacic acid structure

Other nylons are made by varying the molecular length of the diamines and the dibasic acids Nylon-fi. in u.ses sebacic acid (10 carbon atoms), nylon-11 uses an acid from castor oil, and nylon-12 uses butadiene. These variations decrease moisture absorption. Other variations use amines with a ring structure, e.g., the aromatic nylons to give polymers with softening points above 577 F,... 

Oil-Based SINs. The SINs produced were based on a castor oil polyester-urethane and styrene crosslinked with 1 mole percent of technical grade (55%) divinyl benzene (DVB) (7). This structure may be written poly[(castor oil, sebacic acid, TDI)-SIN-(Styfene, DVB)], poly[(CO,SA,TDI)-SIN-(S,DVB)]. Benzoyl peroxide (BP) (0.48%) was used as the free radical initiator for the styrene and 1,4-tolylene-diisocyanate (TDI) was used as the crosslinker for the polyester prepolymer. A 500 ml resin kettle equipped with a N inlet, condenser, thermometer, and high torque stirrer was used as the polymerization reactor. 

Figure 5 General structure of polyanhydrides. R and R can be varied to modify degradation kinetics and profile. The lower frame shows the structure of P(CPP-SA), a polyanhydride copolymer, used in the Gliadel product. Abbreviations SA, sebacic acid CPP, carboxyphen-oxypropane.

T. C. Tranter (36) has studied the binary copolymers based on hexamethylene diamine and -phenylene dipropionic, 3-(/>-carboxy-methyl)phenyl-butyric, 2-(/>-carbomethoxy)phenylpropionic, hydro-quinone diacetic, terephthalic, adipic, or sebacic acids. In spite of the fact that only the copolymers of hexamethylene diamine with/>-phenylene dipropionic and with 2-(/>-carbomethoxy)phenylpropionic acids show a linear softening point composition curve, Tranter claims for isomorphism in the copolymers of all the systems. In fact, their X-ray examination shows that they behave in the same basic manner, the second component dissolving in the lattice of the first until a certain critical concentration is reached, where the lattice structure changes quite abruptly to that of the second component. 

Figure 4.14 The chemical structure of poly [bis(p-carboxyphenoxy)propa ne sebacic acid] and the pathway and products of its metabolism...

The study by Determan et al. [224] focuses on the effects of polymer degradation products on the primary, secondary, and tertiary structure of TT, OVA, and lysozyme after incubation for 0 or 20 days in the presence of ester (lactic acid and glycolic acid) and anhydride [sebacic acid and l,6-bis(p-carboxyphenoxy)hexane] monomers. The structure and antigenicity or enzymatic activity of each protein in the presence of each monomer was quantified. SDS-PAGE, circular dichroism, and fluorescence spectroscopy were used to assess/evaluate the primary, secondary, and tertiary structures of the proteins, respectively. ELISA was used to measure changes in the antigenicity of TT and OVA and a fluorescence-based assay was used to determine the enzymatic activity of lysozyme. TT toxoid was found to be the most stable in the presence of anhydride monomers, while OVA was most stable in the... 

The second approach was applied in the synthesis of fatty acid terminated polyanhydrides. Polyanhydrides based on sebacic acid, and terminated with oleic, stearic, linoleic or lithocholic acid, or combinations of several fatty acids were synthesized 21). The general structure of fatty acid terminated polyanhydrides is shown in Figure 1. 

Researchers at Rutgers University have developed biocompatible polymers that degrade into nonsteroidal anti-inflammatory drugs. For example, the reaction of two equivalents of benzyl salicylate and one equivalent of sebacoyl chloride forms a poly(anhydride ester) called PolyAspirin, which hydrolyzes to salicylic acid (an anti-inflammatory agent) and sebacic acid, which is excreted. This technology can perhaps be used for localized drug delivery at specific sites of injury. What is the structure of PolyAspirin ... 

Aliphatic dibasic acids, such as succinic, adipic, azelaic, and sebacic acids have also been used to make alkyd resins. Their linear and flexible chain structure lends higher flexibility and lower viscosity to the resin than the rigid aromatic rings of phthalic acids. 

Polyanhydrides of terephthalic acid (10.39), isophthalic acid (10.40), and sebacic acid (10.41), were prepared by reaction with phosgene in toluene in the presence of NEtj [1865]. The polymers all have the general structure 10.42 X = l,4-CgH4, 1,3-CgH or (CHj). ... 

The sebacic acid is then polymerized with hexamethlyene diamine as with traditional nylons. Figure 12.5 shows the structure of this polymer. Up to 63% of the material can be derived from castor oil. Table 12.8 shows some important properties as compared to nylon 6. The main properties of tensile strength and modulus, at least in a dry state, are fairly similar. Again, we see how the automotive chemist s input can be utilized in vehicle design and development. 

The synthesis of dimeric fatty acids is based on the reaction between a fatty acid with one double bond (oleic acid) and a fatty acid with two double bonds (linoleic acid) or three double bonds (linolenic acid), at higher temperatures in the presence of solid acidic catalysts (for example montmorillonite acidic treated clays). Dimerised fatty acids (C36) and trimerised fatty acids (C54) are formed. The dimer acid is separated from the trimeric acid by high vacuum distillation. By using fatty dimeric acids and dimeric alcohols in the synthesis of polyesters and of polyester polyurethanes, products are obtained with an exceptional resistance to hydrolysis, noncrystalline polymers with a very flexible structure and an excellent resistance to heat and oxygen (Chapter 12.5). Utilisation of hydrophobic dicarboxylic acids, such as sebacic acid and azelaic acid in polyesterification reactions leads to hydrolysis resistant polyurethanes. 

Normal dicarboxylic acids, HOOC.(CH2)n.COOH, have been more extensively studied, and the structures of several are known. In succinic acid (n = 2), adipic acid (n — 4) and sebacic acid (n — 8), all with an even number of carbon atoms, the molecules are centro-symmetrical and planar, and are linked in the structure into endless chains (fig. 14.16 a) exactly analogous to those found in the ft form of oxalic acid (fig. 14.09 a). The cell dimensions of the acids n — 6 and n — 16 show that they also undoubtedly have the same structure. 

Similar data analysis was applied also to copolymers of sebacic acid with fumaric acid [40], CPH [61], and trimellitimide derivatives [51]. Based on the HNMR analysis, a FA-FA or SA-SA dimer alternating structure (-SA-SA-FA-FA-SA-SA-FA-FA) was suggested for P(FA-SA) 1 1. In the case of copolymers of the asymmetric trimellitimide comonomer (represented by the letters B1 or B2) with the symmetric comonomers sebacic add or CPH (represented by the letter A), 6 diad sequences were expected to be present in the polymer backbone (A-A, A-Bl, A-B2, Bl-Bl, B1-B2, B2-B2) and they were identified by NMR spectroscopy. Due to partially overlapping peaks in some of the copolymers, some assumptions were made. A typical data from this analysis is shown in Table 14. 

Figure 13.7. The chemical structure of sebacic acid plotted using the template Structure.PLE.

The amidation reaction is the basis for the production of the polyamides or nylons. For example, nylon-6,6, which has the structural repeat unit -fHN(CH2)6NHCO(CH2)4CO is made by the condensation of hexa-methylene diamine, H2N(CH2)fiNH2, and adipic add, HOOC(CH2)4COOH, whereas nylon-6,10 results from the comparable reaction between hexa-methylene diamine and sebacic acid, HOOC(CH2)gCOOH. In the labelling of these nylons the first number is the number of carbon atoms in the amine residue and the second the number of carbon atoms in the add residue. Two nylons of somewhat simpler structure, nylon-6 and nylon-11,... 

The structure of Nylon 1010 is shown in Figure 6.217. PAlOlO is 100% renewably sourced. The monomers, 1,10-decamethylene diamine and 1,10-decanedioic acid (sebacic acid), used in PAlOlO are both derived from castor bean oil. PA 1010 offers the typical properties of flexible polyamide with additional benefits such as superior high temperature resistance and lower permeability to fuel and gases. 

---