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E-Caprolactone ring opening polymerization

Converting the "living" prepolymer from oxyl-llthlum to oxy-alumlnum chain end can successfully eliminate the undeslred trans-esterlflcatlon In the e-caprolactone ring-opening polymerization and Its more uniform block polymers with styrene and butadiene were thus prepared. [Pg.170]

D.L., Akkara, J., Swift, G., and Wolk, S. (1995) Enzyme-catalyzed e-caprolactone ring-opening polymerization. Macromolecules, 28 (1), 73-78. [Pg.126]

MNPHP is a well-known irreversible inhibitor of lipases that is highly specific for reaction with active-site serine residues. Thus, MNPHP was selected as the inhibitor to determine, by titration, the fraction of catalytic sites that are accessible and active. Since we are concerned with CALB activity in organic media, inhibition was studied in heptane. LC-MS was used to determine the release of p-nitrophenol (pNP) which corresponds with accessible active sites. To ensure that adsorption of pNP by resins was taken into consideration, pNP concentration was corrected as follows. A fixed quantity of enzyme-free resin was incubated overnight in acetonitrile with different concentrations of j NP. Standard curves of pNP adsorption by each resin as a function of pNP concentration were constructed from LC-MS measurements. MNPHP-inhibited immobilized enzymes were used for e-caprolactone ring-opening polymerizations in toluene (70 C). No conversion of monomer was observed in 30 minutes. Hence, MNPHP titration resulted in complete inhibition of CALB activity. [Pg.159]

Figure 3. Effect of immobilized CALB particle size (given in pm, see legend box in plot) on the time course of e-caprolactone ring-opening polymerizations performed at 70 °C in toluene. (Reproduced from Langmuir 2007, 23, 1381-1387. Copyright 2007 American Chemical Society.)... Figure 3. Effect of immobilized CALB particle size (given in pm, see legend box in plot) on the time course of e-caprolactone ring-opening polymerizations performed at 70 °C in toluene. (Reproduced from Langmuir 2007, 23, 1381-1387. Copyright 2007 American Chemical Society.)...
Reference 34. MNPHP-inhibited immobilized enzymes were used for e-caprolactone ring-opening polymerizations in toluene (70 °C). No conversion of monomer was observed in 30 minutes. Hence, MNPHP titration resulted in complete inhibition of CALB activity. [Pg.170]

The effects of organic solvents on lipase reactivity are complex. Thus, it is difficult to predict the behavior of different lipases in the same solvent system or of different solvents with the same lipase. Previous work in our laboratory studied solvent properties, such as solvent log P (logarithm of partition coefficient), and its correlation to Novozyme-435 activity for E-caprolactone ring-opening polymerizations. Of the solvents studied, those with log P values... [Pg.320]

Poly(f -caprolactone) (PCL), the most representative member of this polyester family, is obtained by the ring-opening polymerization of e-caprolactone. It is a low-7 (60°C), low-Tg (—60°C) semicrystalline polyester that presents mechanical properties resembling those of low-density polyethylene (Table 2.10). [Pg.43]

Preparation and characteristics of ABA type polycaprolactone-b-polydimethyl-siloxane block copolymers have been recently reported 289). In this study, ring-opening polymerization of e-caprolactone was achieved in melt, using a hydroxybutyl terminated PSX as the initiator and a catalytic amount of stannous octoate. Reactions were completed in two steps as shown in Reaction Scheme XIX. [Pg.51]

In recent years homoleptic lanthanide(III) tris(amidinates) and guanidinates have been demonstrated to exhibit extremely high activity for the ring-opening polymerization of polar monomers such as e-caprolactone and trimethylene... [Pg.240]

Ring-opening polymerization of 2-methylene-l,3-dioxepane (Fig. 6) represents the single example of a free radical polymerization route to PCL (51). Initiation with AIBN at SO C afforded PCL with a of 42,000 in 59% yield. While this monomer is not commercially available, the advantage of this method is that it may be used to obtain otherwise inaccessible copolymers. As an example, copolymerization with vinyl monomers has afforded copolymers of e-caprolactone with styrene, 4-vinylanisole, methyl methacrylate, and vinyl acetate. [Pg.80]

Various cyclic esters have been subjected to hpase-catalyzed ring-opening polymerization. Lipase catalyzed the ring-opening polymerization of 4- to 17-membered non-substituted lactones.In 1993, it was first demonstrated that medium-size lactones, 8-valerolactone (8-VL, six-membered) and e-caprolactone (e-CL, seven-membered), were polymerized by lipases derived from Candida cylindracea, Burkholderia cepacia (lipase BC), Pseudomonas fluorescens (lipase PF), and porcine pancreas (PPL). °... [Pg.207]

Optically active polyesters were synthesized by lipase CA-catalyzed ring-opening polymerization of racemic 4-methyl or ethyl-e-caprolactone. The (5 )-isomer was enantioselectively polymerized to produce the polyester with >95% ee. Quantitative reactivity of 4-substituted e-caprolactone using lipase CA as catalyst was analyzed. The polymerization rate decreased by a factor of 2 upon the introduction of a methyl substitutent at the 4-position. Furthermore, 4-ethyl-8-caprolactone polymerized five times slower than the 4-methyl-8-caprolactone. This reactivity difference is strongly related to the enantioselectivity. Interestingly, lipase CA displayed 5 -selectivity for 4-methyl or ethyl-8-caprolactone, and the enantioselectivity was changed to the (f )-enantiomer in the case of 4-propyl-8-caprolactone. [Pg.219]

The cationic ring opening polymerization of e-caprolactone, CL, and 8-valerolactone, VL, was investigated using n-Bu0H/HCl-Et20 as the initiation system [56]. It was observed that narrow molecular weight distribution samples were obtained. These results were combined with those previously... [Pg.35]

Table 2 Ring-opening polymerization of lactones initiated by lanthanide complexes (CL = e-caprolactone LA = lactide TMC = trimethylene carbonate). [Pg.50]

Over the years we have developed methods for the direct synthesis of hydrolytically and/or enzymatically degradable microspheres by ring-opening polymerization of e-caprolactone and lactides [6-12]. The diameters of these microspheres are usually less than 3 xm. In this chapter we discuss... [Pg.269]

Surface-initiated ring-opening polymerization of e-caprolactone on pCP SAM initiators equipped with an oligo-ethylenoxide function is reported by Hawker et al. [346]. Choi and hanger used a similar SAM initiator system to polymerize L-lactide [347]. [Pg.433]

Materials. PCL and polypropiolactone (PPL) were prepared by ring opening polymerization of e -caprolactone ( ) and S -propiolactone respectively in benzene in a nitrogen atmosphere at 60 C with a di-... [Pg.136]

Bailey WJ, Ni Z, Wu S-R (1982) Synthesis of poly-e-caprolactone via a free radical mechanism. Free radical ring opening polymerization of 2-methylene-l,3-dioxepane. J Polym Sci A Polym Chem 20 3021-3030... [Pg.208]

McLain SJ, Drysdale NE (1992) Living ring-opening polymerization of e-caprolactone by yttrium and lanthanide alkoxides. Polymer Preprints, American Chemical Society 33(1) 174-175... [Pg.209]

Martin E, Dubois P, Jerome R (2000) Controlled ring-opening polymerization of e-caprolactone promoted by in situ formed yttrium alkoxides. Macromolecules 33 1530-1535... [Pg.209]

Oshimura M, Takasu A (2010) Controlled ring-opening polymerization of E-caprolactone catalyzed by rare-earth perfluoroalkanesulfonates and perfluoroalkanesulfonimides. Macromolecules 43 2283-2290... [Pg.210]

Stassin F, Halleux O, Jerome R (2001) Ring-opening polymerization of E-caprolactone in supercritical carbon dioxide. Macromolecules 34 775-781... [Pg.210]

Shueh ML, Wang Y-S, Fluang B-H, Kuo C-Y, Lin C-C (2004) Reactions of 2,2 -methylenebis(4-chloro-6-isopropyl-3-methylphenol) and 2,2 -ethylenebis(4,6-di-tert-butylphenol)with Mg"Bt2 efficient catalysts for the ring-opening polymerization of e-caprolactone and L-lactide. Macromolecules 37 5155-5162... [Pg.211]

Abraham GA, Gallardo A, Lozano AE, San RJ (2000) E-caprolactone/ZnCL complex formation characterization and ring-opening polymerization mechanism. J Polym Sci A Polym Chem 38 1355-1365... [Pg.211]

Liu J, Liu L (2004) Ring-opening polymerization of e-caprolactone initiated by natural amino acids. Macromolecules 37 2674—2676... [Pg.212]

Knani D, Gutman AL, Kohn DH (1993) Enzymatic polyesterification in organic media. Enzyme-catalyzed synthesis of linear polyesters. I. Condensation polymerization of linear hydroxyester. II. Ring-opening polymerization of e-caprolactone. J Polym Sci A Polym Chem 31 1221-1232... [Pg.213]

Loeker EC, Duxbury CJ, Kumar R, Gao W, Gross RA, Howdle SM (2004) Enzyme-catalyzed ring-opening polymerization of e-caprolactone in supercritical carbon dioxide. Macromolecules 37 2450-2453... [Pg.213]

Raquez J-M, Degee P, Narayan R, Dubois P (2000) Coordination-insertion ring-opening polymerization of l,4-dioxan-2-one and controlled synthesis of diblock copolymers with e-caprolactone. Macromol Rapid Commun 21 1063-1071... [Pg.214]

Detrembleur C, Mazza M, Halleux O, Lecomte P, Mecerreyes D, Hedrick JL, Jerome R (2000) Ring-opening polymerization of y-Bromo-E-caprolactone a novel route to functionalized aliphatic polyesters. Macromolecules 33 14-18... [Pg.214]

Liu M, Vladimirov N, Frechet JMJ (1999) A new approach to hyperbranched polymers by ring-opening polymerization of an AB Monomer 4-(2-hydroxyethyl)-e-caprolactone. Macromolecules 32 6881-6884... [Pg.216]

Aldonolactones serve as suitable monomers for the generation of homo- and copolymers, especially through ring-opening polymerization (ROP). Among them are the carbohydrate-analogs of s-caprolactone, i.e., aldono-1,6-lactones. The first example of such derivatives and further ROP was reported by Galbis and co-workers [61], see also chapter, Synthetic polymers from readily available monosaccharides ... [Pg.30]

Here we discuss dispersion polymerizations that are not related to vinyl monomers and radical polymerization. The first one is the ring-opening polymerization of e-caprolactone in dioxane-heptane (30). A graft copolymer, poly(dodecyl acrylate)-g-poly(e-caprolactone), is used as a stabilizer. The polymerization proceeds via anionic or pseudoanionic mechanism initiated by diethylaluminum ethoxide or other catalysts. The size of poly(caprolactone) particles depends on the composition of stabilizer, ranging from 0.5 to 5 i,m. Lactide was also polymerized in a similar way. Poly(caprolactone) and poly(lactide) particles with a narrow size distribution are expected to be applied as degradable carriers of drugs and bioactive compounds. [Pg.620]

The Novozym 435-catalyzed ring-opening polymerization of e-caprolactone shown in Figure 6.2 was also performed in the presence of methyl or ethyl gluco-pyranosides. In this way, polyesters with low polydispersity index (PDI) values and initiated by alkyl glucopyranosides (acylated at their primary OH) could be prepared [48]. [Pg.152]


See other pages where E-Caprolactone ring opening polymerization is mentioned: [Pg.10]    [Pg.10]    [Pg.394]    [Pg.24]    [Pg.335]    [Pg.71]    [Pg.73]    [Pg.209]    [Pg.176]    [Pg.56]    [Pg.138]    [Pg.34]    [Pg.494]    [Pg.211]    [Pg.211]    [Pg.212]    [Pg.616]    [Pg.665]   


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