Kinetics of poly

Fig. 7a, b. Kinetics of poly(p-nitrophenyl acrylate) chemical adsorption on aminopropyl-Aerosil at 25 °C in dimethylsulphoxide. Filled circles ester group content (pmol/g support), empty c/rc/ei p-nitrophenol release (pmol/g support), a — l%solution b — 5% solution [55]... 

Figure 3A shows the kinetics of poly(3HB) accumulation for several specific formation rates, depending on the duration of accumulation. As can be seen, the poly(3HB) content approaches a value of 100% asymptotically. However - and this might be considered trivial - how closely the upper limit is reached is ruled by the fact that an increasing content requires increasing synthesis while the capacity is decreasing (Fig. 3B). Economically acceptable contents are reached after very different periods of accumulation this means that the specific formation rate is a very important parameter which depends on the organism involved and, with a given genotype, on the substrate used. Hence we should fo-...

The authors [1] studied kinetics of poly (amic acid) (PAA) solid-state imidization both in the presence of nanofiller (layered silicate Na+-montmorillonite) and without it. It was found, that temperature imidization 1] raising in range 423-523 K and nanofiller contents Wc increase in range 0-7 phr result to essential imidization kinetics changes expressed by two aspects by essential increase of reaction rate (reaction rate constant of first order k increases about on two order) and by raising of conversion (imidization) limiting degree Q im from about 0,25 for imidization reaction without filler at 7 i=423 K up to 1,0 at Na -montmorillonite content 7... 

Shi, Y. and Jabarin, S. A., Transesterification reaction kinetics of poly(ethylene terephthalate)/poly(ethylene 2,6-naphthalate) blends, J. Appl. Polym. Sci., 80, 2422-2436 (2001). 

Chuah, H. H., Vinson, R. W. and Ulzelmeier, C. W., The Kinetics of Poly(Propylene Terephthalate) Solid-state Polymerization in Research Awareness Bulletin, Shell Chemical Company, July 1993, Houston, TX, pp. 101-103. 

This equation is a result of considering the adsorption and desorption kinetics described in the equilibrium which establishes the Langmuir equation 9.31. Chen, et al. [68] have studied the adsorption kinetics of poly(acrylic add) onto BaTiOs from aqueous solution. Their results are given in Table 9.13. The adsorption kinetics are faster in the case of pH 10.5 because the n ative charge on the polymer attracts the positive charge on the BaTiOg surface. At pH 1.5 there is no charge on the polymer, thus diffusion to the surface is not enhanced. 

Spontaneous orientation of the molecules occurs on transition to the nematic state. Experiments of Spencer and Berry [36] on polymerization kinetics of poly (p-phenylene benzo bis thiazole) (PBT) in polyphosphoric acid, in which an isotropic to nematic transition occurred during polymerization, surprisingly, showed no sudden change in the polymerization rate. The reasons for this are not apparent. An interesting result of the study is that the polymerization reaction may be diffusion controlled even in the nematic phase. 

Application of the Computer to Degradation Kinetics of Poly(vinyl Halides)... 

Computer programs have been used to correlate the degradation kinetics of poly(vinyl halides) assuming a kinetic model that is based on the zipper mechanism. Best fit values of the parameters of the kinetic model allow reproduction of a degradation with an error that is usually less than 0.6% per point. 

The storage of voluminous run data in a readily available form and the obtaining of best fit values of kinetic parameters have been useful in the better understanding of the degradation kinetics of poly(vinyl halides). ... 

Thermal decomposition kinetics of poly (trirnethylene terephthalate). X-S. Xue Song Wang, X-G. Xin-Gui li, D. Deyue Yan. /Polymer degradation and stability 2000, 69 3 361-372. 

Y. Kaneko, R. Yoshida, K. Sakai, Y. Sakurai and T. Okano, Temperature-responsive shrinking kinetics of poly(Y-isopropylacrylamide) copolymer gels with hydrophilic and hydrophobic comonomers, J. Membr. Sci., 1995, 101, 13 Y.H. Lim, D. Kim and D.S. Lee, Drug releasing characteristics of thermo- and pH-sensitive interpenetrating polymer networks based on poly(W-isopropylacrylamide), J. Appl. Polym. Sci., 1997,... 

Boskhomdzhiev, A. R et al. Biochem. (Moscow) Supp. Ser B Biomed. Chem. 2010, 4(2), 177-183. Biodegradation kinetics of poly(3-hydroxybutyrate)-based biopolymer systems. 

H. H. Yang, J. He, and B. R. Liang. Transesteriflcation kinetics of poly-(ethylene terephthalate) and poly(ethylene 2,6-naphthalate) blends with the addition of 2,2 -bis(l,3-oxazoline). J. Polym. Set, Part B Polym. Phys., 39 (21) 2607-2614, November 2001. 

Curro et al. [1981] followed a similar procedure in studies of the aging kinetics of poly(methyl methacrylate) (PMMA). For predicting the shift factors of aging experiments at 23°C, the authors computed from PVT the free-volume function, h = h P, V), and then substituted these into Doolittle s equation (6.63). The resulting prediction agreed with the experimental values, contrasting with the inadequacy of the WLF relation. Next, the polymer aging process was modeled as a diffusion of free volume [Curro et al., 1982]. 

H. Yi, G. Jianjun, L.F. Kazuro, H. Ryotaro, L.R Anca, R.W. William, Tailoring the degradation kinetics of poly(ester carbonate urethane)urea thermoplastic elastomers for tissue engineering scaffolds, Biomaterials il (15) (2010) 4249 258. 

The kinetics of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers have been intensively studied by T-jump experiments with light scattering detection [115, 126-130]. PEO-PPO-PEO triblock copolymers form micelles in aqueous solution, with PPO as the core forming hydrophobic block. Above the critical micelle concentration (cmc) and critical micelle temperature there exists a transition region of AT 10-15 C where... 

Wang, Q., Y. Zhao, et al. (2009). Thermosensitive phase transition kinetics of poly(N-isopropylacryl amide-co-acrylamide) microgel aqueous dispersions. Journal of... 

Vasanthakumari, R. and Pennings, A.J. (1983) Crystallization kinetics of poly(L-lactic acid). Polymer, 24,175-178. 

Pan, R, Zhu, B., Kai, W. et al. (2008) Effect of crystallization temperature on crystal modifications and crystallization kinetics of poly(L-lactide). Journal of Applied Polymer Science, 107, 54-62. 

Marega, C., Marigo, A., Di Noto, V. et al. (1992) Stiucture and crystallization kinetics of poly(L-lactic acid). Makromolekulare Chemie, 193, 1599-1606. 

Vaidya, U. R. Nadkami, V. M. Polyester polyols from glycolyzed PET waste effect of glycol type on kinetics of poly esterification. J. Appl. Polymer Sci., 1989, 38(6), 1179-1190. 

Nesterov, A.E., Lipatov, Y.S., Horichko, V.V., Gritsenko, O.T. Filler effects on the compatibility and phase separation kinetics of poly(vinyl acetate)-poly(methyl methacrylate) mixtures. Polymer 33(3), 619-622 (1992)... 

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