Polylactide composites

Pillai, S. K., Ramontja, J., and Ray, S. S. (2011). Amine functionalization of carbon nanotubes for the preparation of CNT based polylactide composites-a comparative study. 

N. Ignjatovic, D. Uskokovic, Synthesis and appUcation of hydroxy-apatite/polylactide composite biomaterial, Appl. Surf. Sd. 238 (1) (2004) 314-319. 

Wu, D., Wu, L., Zhang, M., Zhao, Y. Viscoelasticity and thermal stability of polylactide composites with various functionalized carbon nanotubes. Polytn. Degrad. Stab. 93, 1577-1584 (2008)... 

Pluta, M., Murariu, M., Ferreira, A.D.S. et al. (2007) Polylactide compositions. 11. Correlation between morphology and main properties of PLA/calcium sulfate composites. Journal of Polymer Science Part B Polymer Physics, 45, 2770-2780. 

Bleach, N.C., Nazhat, S.N., Tanner, K.E. et al. (2002) Effect of filler content on mechanictil and dynamic mechanical properties of paiticulate biphasic calcium phosphate - Polylactide composites. Biomaterials. 23, 1579-1585. 

Mucha, M. Ludwiczak, S., Water Sorption by Biodegradable Chitosan/Polylactide Composites., Polish Chitin Society, 2007, Monograph XII, pp41-8. 

R.H. Hu, M.Y. Sun and J.K. Lim, Moisture absorption, tensile strength and microstructure evolution of short jute fiber/polylactide composite in hygrothermal environment. Mater. Des. 31, 3167-3173 (2010). 

Wu D, Lv Q, Feng S, Chen J, Chen Y, Qiu Y, Yao X (2015) Polylactide composite foams containing caibon nanotubes and caibon black Synergistic effect of filler on electrical conductivity. Carbon 95 380-387... 

Ignjatovic N, Uskokovic D (2004) Synthesis and application of hydroxyapatite/polylactide composite biomaterial. Appl Surface Sci 238 314-319... 

Bleach NC, Nazhat SN, Tanner KE, KeUomaki M, Tormala P. Effect of fiUer content on mechanical and dynamic mechanical properties of particulate biphasic calcium phosphate polylactide composites. Biomaterials 2002 23 1579-1585. 

Poly(ethylene terephthalate), the predominant commercial polyester, has been sold under trademark names including Dacron (Du Pont), Terylene (ICI), Eortrel (Wellman), Trevira (Hoechst-Celanese), and others (17). Other commercially produced homopolyester textile fiber compositions iaclude p oly (1,4-cyc1 oh exa n e- dim ethyl en e terephthalate) [24936-69-4] (Kodel II, Eastman), poly(butylene terephthalate) [26062-94-2] (PBT) (Trevira, Hoechst-Celanese), and poly(ethylene 4-oxyben2oate) [25248-22-0] (A-Tell, Unitika). Other polyester homopolymer fibers available for specialty uses iaclude polyglycoHde [26124-68-5] polypivalolactone [24937-51-7] and polylactide [26100-51-6],... 

Polylactide (PLA)-CaS04 composites toughened with low molecular weight and polymeric ester-like plasticizers and related performances. European Polymer Journal 44 3842-3852. 

Bielaet al. (2002,2003) prepared and analyzed linear and star-shaped polylactides. Using LCCC, star-shaped samples were separated with regard to the number of arms. Essentially, this separation was driven by the number of hydroxy groups that constituted the end group of each arm. Two-dimensional LC was used to show that the LCCC separation was exclusively driven by chemical composition irrespective of molar mass. 

All liposphere formulations prepared remained stable during the 3-month period of the study, and no phase separation or appearance of aggregates were observed. The difference between polymeric lipospheres and the standard liposphere formulations is the composition of the internal core of the particles. Standard lipospheres, such as those previously described, consist of a solid hydrophobic fat core composed of neutral fats like tristearin, whereas, in the polymeric lipospheres, biodegradable polymers such as polylactide or polycaprolactone were substituted for the triglycerides. Both types of lipospheres are thought to be stabilized by one layer of phospholipid molecules embedded in their surface. 

Hu et al. showed a decrease in electrical resistivity of PVA by four orders of magnitude with a percolation threshold of 6 wt% [68], while biodegradable polylactide-graphene nanocomposites were prepared with a percolation threshold as low as 3 5wt% [46]. For polystyrene-graphene composites, percolation occurred at only 0.1 °/o of graphene filler, a value three times lower than those for other 2D-filler [69]. Figure 6.7(b) shows the variation of conductivity of the polystyrene-graphene composite with filler content. A sharp increase in conductivity occurs at 0.1 % (the percolation threshold) followed by a saturation. The inset shows the four probe set up for in-plane and trans-... 

Furthermore, such monomers can be readily emulsified by dissolving in volatile solvents such as methylene chloride and chloroform. Uniform polylactide particles, and composite polystyrene (PST) and polymethyl methacrylate (PMMA) particles were produced by solvent evaporation [84-86]. 

Narrow distribution in the backbone length as well as in the chemical composition or the branch frequency may be expected from a living-type copolymerization between a macromonomer and a comonomer provided the reactivity ratios are close to unity. This appears to have been accomplished to some extent with anionic copolymerizations with MMA of methacrylate-ended PMMA, 29, and poly(dimethylsiloxane) macromonomers, 30, which were prepared by living GTP and anionic polymerization, respectively [50,51]. Recent application [8] of nitroxide (TEMPO)-mediated living free radical process to copolymerizations of styrene with some macromonomers such as PE-acrylate, la, PEO-methacr-ylate, 27b, polylactide-methacrylate, 28, and poly(e-caprolactone)-methacrylate, 31, may be a promising approach to this end. 

Other examples of successful combinations of liquid chromatography and MALDI-TOF have been reported by Kruger et al. who separated linear and cyclic fractions of polylactides by LC-CC [184]. Just et al. were able to separate cyclic siloxanes from linear silanols and to characterize their chemical composition [185]. The calibration of an SEC system by MALDI-TOF was discussed by Mon-taudo et al. [186]. Poly( dimethyl siloxane) (PDMS) was fractionated by SEC into different molar mass fractions. These fractions were subjected to MALDI-TOF for molar mass determination. The resulting peak maximum molar masses were... 

Plackett D, Andersen TL, Pedersen WB, Nielsen L (2003) Biodegradable composites based on L-polylactide and jute fibres. Compos Sci Technol 63(9) 1287-1296 Sebastien F, Stephane G, Copinet A, Coma V (2006) Novel biodegradable films made from chitosan and poly(lactic acid) with antifungal properties against mycotoxinogen strains. Carbohydr Polym 65(2) 185-193... 

Roether, J.A., Boccaccini, A.R., Hench, L.L., Maquet, V., Gautier, S., and Jerome, R. (2002) Development and in vitro characterisation of novel bioresorbable and bioactive composite materials based on polylactide foams and bioglass for tissue engineering applications. Biomaterials, 18, 3871-3878. 

The above mentioned scaffolds were made completely of the ceramic materials. Other potential materials which could be used to fabricate a novel construct for the repair of ciitical-sized bone defects is a novel material made of biodegradable polymer reinforced with ceramics particles. The properties of such a composite depend on 1) properties of the polymer used for the matrix and properties of the ceramics used for the reinforcement, 2) composition of the composite (i.e. content of ceramic particles) and 3) size, shape and arrangement of the particles in the matrix. Several polymer-composite composites have been used for scaffolds fabrication including polylactide (PLA) and polycaprolacton (PCL) reinforced with calcium phosphate (CaP) micro and nanoparticles. Authors proposed a novel composite material by blending copolymer -Poly(L-lactide-co-D,E-lactide) (PLDLLA) a copolymer with a ceramic - Tri-Calcium Phosphate... 

Homodecoupled NMR spectra can be used to quantitatively determine the composition of D-lactide and meso-lactide stereoisomer impurities in polylactide containing predominantly L-lactide [5]. 

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