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Polymeric sebacate

Polymeric sebacate (G-25, P-1030) NR— Not recommended. 1—5 Excellent-to-poOT rating. Polyester 160,000 NR NR... [Pg.391]

Aqueous caprolactam is polymerized alone and in the presence of sebacic acid (S) or hexamethylenediamine (H).t After a 24-hr reaction time, the polymer is isolated and the end groups are analyzed by titrating the carboxyl groups with KOH in benzyl alcohol and the amino groups with p-toluenesulfonic acid in trifluoroethanol. The number of milliequivalents of carboxyl group per mole caprolactam converted to polymer, [A ], and the number of milliequivalents of amino groups per mole caprolactam converted to polymer, [B ], are given below for three different runs ... [Pg.32]

Reimschuessel and Deget polymerized caprolactam in sealed tubes containing about 0.0205 mol HjO per mole caprolactam. In addition, acetic acid (V), sebacic acid (S), hexamethylene diamine (H), and trimesic acid (T) were introduced as additives into separate runs. The following table lists (all data per mole caprolactam) the amounts of additive present and the analysis for end groups in various runs ... [Pg.342]

Plasticizers. Monomeric (mol wt 250—450) plasticizers (qv) are predominantiy phthalate, adipate, sebacate, phosphate, or trimeUitate esters. Organic phthalate esters like dioctyl phthalate (DOP) are by far the most common plasticizers in flexible PVC. Phthalates are good general-purpose plasticizers which impart good physical and low temperature properties but lack permanence in hot or extractive service conditions and are therefore sometimes called migratory plasticizers. Polymeric plasticizers (mol wt up to 5000 or more) offer an improvement in nonmigratory permanence at a sacrifice in cost, low temperature properties, and processibiHty examples are ethylene vinyl acetate or nitrile polymers. [Pg.327]

Plasticizers can be classified according to their chemical nature. The most important classes of plasticizers used in rubber adhesives are phthalates, polymeric plasticizers, and esters. The group phthalate plasticizers constitutes the biggest and most widely used plasticizers. The linear alkyl phthalates impart improved low-temperature performance and have reduced volatility. Most of the polymeric plasticizers are saturated polyesters obtained by reaction of a diol with a dicarboxylic acid. The most common diols are propanediol, 1,3- and 1,4-butanediol, and 1,6-hexanediol. Adipic, phthalic and sebacic acids are common carboxylic acids used in the manufacture of polymeric plasticizers. Some poly-hydroxybutyrates are used in rubber adhesive formulations. Both the molecular weight and the chemical nature determine the performance of the polymeric plasticizers. Increasing the molecular weight reduces the volatility of the plasticizer but reduces the plasticizing efficiency and low-temperature properties. Typical esters used as plasticizers are n-butyl acetate and cellulose acetobutyrate. [Pg.626]

Paraplex. A trademark for a group of alkyd type polymeric materials known as polyester resins. These resins are primarily long chain polybasic acids esterified with polyhydric alcohols such as glycol sebacate, glycerol, or ethylene glycol. Some are oil-modified while others are unmodified polyesters... [Pg.489]

PA-6,10 is synthesized from 1,6-hexamethylenediamine and sebacic acid, and PA-6,12 from 1,6-hexamethylenediamine and dodecanedioic acid. The melt synthesis from their salts is very similar to PA-6,6 (see Example 1). These diacids are less susceptible to thermal degradation.55 PA-6,10 can also be synthesized by interfacial methods at room temperature starting with the very reactive sebacyl dichloride.4 35 A demonstration experiment for interfacial polycondensation without stirring can be carried out on PA-6,10. In this nice classroom experiment, a polymer rope can be pulled from the polymerization interface.34... [Pg.170]

Alkyl esters often show low reactivity for lipase-catalyzed transesterifications with alcohols. Therefore, it is difficult to obtain high molecular weight polyesters by lipase-catalyzed polycondensation of dialkyl esters with glycols. The molecular weight greatly improved by polymerization under vacuum to remove the formed alcohols, leading to a shift of equilibrium toward the product polymer the polyester with molecular weight of 2 x 10" was obtained by the lipase MM-catalyzed polymerization of sebacic acid and 1,4-butanediol in diphenyl ether or veratrole under reduced pressure. ... [Pg.213]

The enzymatic synthesis of polyesters from activated diesters was achieved under mild reaction conditions. The polymerization of bis(2,2,2-trichloroethyl) glutarate and 1,4-butanediol proceeded in the presence of PPL at room temperature in diethyl ether to produce the polyesters with molecular weight of 8.2 x 10. Vacuum was applied to shift the equilibrium forward by removal of the activated alcohol formed, leading to the production of high molecular weight polyesters. The polycondensation of bis(2,2,2-trifluoroethyl) sebacate and aliphatic diols took place using lipases BC, CR, MM, and PPL as catalyst in diphenyl ether. Under the... [Pg.213]

Room-temperature ionic liquids have received much attention as green designer solvents. We first demonstrated that ionic liquids acted as good medium for lipase-catalyzed production of polyesters. The polycondensation of diethyl adipate and 1,4-butanediol using lipase CA as catalyst efficiently proceeded in l-butyl-3-methylimidazolinium tetrafluoroborate or hexafluorophosphate under reduced pressure. The polymerization of diethyl sebacate and 1,4-butanediol in l-butyl-3-methylimidazolinium hexafluorophosphate took place even at room temperature in the presence of lipase BC. ... [Pg.218]

Many common polymers, polymeric additives and lubricants oxidise so rapidly after impact in liquid oxygen that they are hazardous. Of those tested, only acrylonitrile-butadiene, poly(cyanoethylsiloxane), poly(dimethylsiloxane) and polystyrene exploded after impact of 6.8-95 J intensity (5-70 ft.lbf). All plasticisers (except dibutyl sebacate) and antioxidants examined were very reactive. A theoretical treatment of rates of energy absorption and transfer is included [1], Previously, many resins and lubricants had been examined similarly, and 35 were found acceptable in liquid oxygen systems [2],... [Pg.1857]

Lipase-catalyzed polymerization of divinyl adipate or divinyl sebacate with a, co-glycols with different chain length has been reported [40]. Lipases CA, MM, PC, and PF showed high catalytic activity toward the polymerization. A combination of divinyl adipate, 1,4-butanediol, and lipase PC afforded the polymer with number-average molecular weight (Mn) of 2.1 x 104. The yield of the polymer from divinyl sebacate was higher than that from divinyl adipate, whereas the opposite tendency was observed in the polymer molecular weight. [Pg.245]

End-functional polymers were also synthesized by lipase-catalyzed polymerization of DDL in the presence of vinyl esters [103,104]. The vinyl ester acted as terminator ( terminator method ). In using vinyl methacrylate (12.5 mol % or 15 mol % based on DDL) and lipase PF as terminator and catalyst, respectively, the quantitative introduction of methacryloyl group at the polymer terminal was achieved to give the methacryl-type macromonomer (Fig. 12). By the addition of divinyl sebacate, the telechelic polyester having a carboxylic acid group at both ends was obtained. [Pg.254]

When heating treatments are applied to obtain stand oils, the following chemical modifications are likely to occur cross-linking of triacylglycerols, isomerization of double bonds, and formation of dimers through Diels-Alder cyclization [50,51]. As a result of double bond isomerization, the amounts of suberic and sebacic acids increase with respect to azelaic acid. Consequently, the ratio of suberic acid to azelaic acid may help to indicate a pre-polymerized oil [52,53]. [Pg.199]

Polyanhydrides based on unsaturated and fatty acid-derived monomers are shown in Table III. Poly(fumaric acid) (PFA) was fist synthesized by Domb et al. (1991) by both melt polycondensation and solution polymerization. The copolymer of fumaric acid and sebacic acid (P(FA-SA)) has been synthesized and characterized (Domb et al., 1991 Mathiowitz et al., 1990b). The mucoadhesive properties of this polymer... [Pg.177]

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. [Pg.239]

Polyamides, commonly known as nylons, may safely be used to produce articles intended for application in processing, handling, and packaging of food, including for products intended to be cooked directly in their packages. Nylon resins are manufactured by condensation of hexyamethylenediamine and adipic acid (nylon 66) or sebacic acid (nylon 610), by the polymerization process, e.g., of co-laurolactam (nylon 12), or by condensation and polymerization, e.g., nylon 66 salts and s-caprolactam. [Pg.320]


See other pages where Polymeric sebacate is mentioned: [Pg.93]    [Pg.94]    [Pg.393]    [Pg.93]    [Pg.94]    [Pg.393]    [Pg.64]    [Pg.333]    [Pg.44]    [Pg.213]    [Pg.215]    [Pg.220]    [Pg.221]    [Pg.221]    [Pg.222]    [Pg.4]    [Pg.25]    [Pg.243]    [Pg.246]    [Pg.308]    [Pg.173]    [Pg.182]    [Pg.186]    [Pg.189]    [Pg.191]    [Pg.238]    [Pg.190]    [Pg.89]    [Pg.92]    [Pg.135]    [Pg.156]    [Pg.157]    [Pg.6]    [Pg.109]   
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