Poly temperature dependence

Materials that typify thermoresponsive behavior are polyethylene—poly (ethylene glycol) copolymers that are used to functionalize the surfaces of polyethylene films (smart surfaces) (20). When the copolymer is immersed in water, the poly(ethylene glycol) functionaUties at the surfaces have solvation behavior similar to poly(ethylene glycol) itself. The abiUty to design a smart surface in these cases is based on the observed behavior of inverse temperature-dependent solubiUty of poly(alkene oxide)s in water. The behavior is used to produce surface-modified polymers that reversibly change their hydrophilicity and solvation with changes in temperatures. Similar behaviors have been observed as a function of changes in pH (21—24). 

Liquid Third Phase. A third Hquid with coUoidal stmcture has been a known component in emulsions since the 1970s (22) for nonionic surfactants of the poly(ethylene glycol) alkylaryl ether type. It allows low energy emulsification (23) using the strong temperature dependence of the coUoidal association stmctures in the water—surfactant—hydrocarbon systems. 

Temperature dependence (related to the temperature dependence of the conformational structure and the morphology of polymers) of the radiation effect on various fluoropolymers e.g., poly (tetrafluoroethylene-co-hexafluoropropylene), poly(tetrafluoroethylene-co-perfluoroalkylvinylether), and poly(tetrafluoroethylene-co-ethylene) copolymers has been reported by Tabata [419]. Hill et al. [420] have investigated the effect of environment and temperature on the radiolysis of FEP. While the irradiation is carried out at temperatures above the glass transition temperature of FEP, cross-linking reactions predominate over chain scission or degradation. Forsythe et al. [421]... 

YH Bae, T Okano, SW Kim. Temperature dependence of swelling of crosslinked poly(N,N-alkyl substituted acrylamides) in water. J Polym Sci B 28 923-936, 1990. 

Figure 5 Temperature dependence of ionic conductivity for poly(organoboron halide)-imidazole complexes in the presence of various lithium salts.

Efremova NV, Sheth SR, Leckband DE (2001) Protein-induced changes in poly(ethylene glycol) brushes molecular weight and temperature dependence. Langmuir 17 7628-7636... 

The first report on the temperature-dependent solubility of PVCL was published in 1968 by Solomon et al. [271]. Up to the 1990s, most studies on PVCL originated from groups in the former Soviet Union. These early studies are reviewed in Kirsh s book [151] on poly(N-vinylamides). Recently, PVCL and its solution properties have been scrutinised anew, in view of the noted bio-... 

Fig. 5 Temperature dependences of the full width of NMR signal (A1/2 v) at half maximum measured for water protons in D2O solutions of the fractions a p and b s of poly(NVCl-co-NVIAz) synthesized at 65 °C from the feed with initial ratio of comonomers 85 15 (mole/mole) (the data from [27])...

Unfortunately, data on the temperature-dependent solution behaviour of these fractions are not available to date, although it will be of considerable interest to compare, e.g., HS-DSC and NMR results for the bound and unbound fractions of poly(NiPAAm-co-NVIAz) over the temperature range characteristic of the conformational and phase transitions of NiPAAm homopolymers and copolymers. 

Figure 4.13 (a) Temperature dependence of dissymmetry ratios of poly ( S )-3,7-dimethy locty 1-3-methylbutylsilane (16) (three different Mw samples) and poly (5) -3,7-dimethyloctyl-2-methyl-propylsilane (17) (a purely P helix) in isooctane, (b) Temperature dependence of P and M populations of 16 in isooctane by reference to the regression curve of gabs values in 17. 

M. Ariu, D.G. Lidzey, M. Sims, A.J. Cadby, P.A. Lane, and D.D.C. Bradley, The effect of morphology on the temperature-dependent photoluminescence quantum efficiency of the conjugated polymer poly(9,9-dioctylfluorene), J. Phys. Condens. Matter, 14 9975-9986, 2002. 

Another interesting chiral chain end effect is exhibited by the helical polymer block co-polymer, poly(l,l-dimethyl-2,2-di-/z-hexylsilylene)- -poly(triphenylmethyl methacrylate), reported by Sanji and Sakurai (see Scheme 7) and prepared by the anionic polymerization of a masked disilene.333 The helical poly(triphenylmethyl methacrylate) block (PTrMA) is reported to induce a PSS of the same sign in the poly(di- -propylsilylene) block in THF below — 20 °C, and also in the solid state, by helicity transfer, as evidenced by the positive Cotton effect at 340 nm, coincident with a fairly narrow polysilane backbone UV absorption characteristic of an all-transoid-conformation. This phenomenon was termed helical programming. Above 20°C, the polysilane block loses its optical activity and the UV absorption shifts to 310 nm in a reversible, temperature-dependent effect, due to the disordering of the chain, as shown in Figure 45. 

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