Gordon-Taylor copolymer

The Gordon-Taylor copolymer equation (Equation 4) has been applied to the Tg data in this study to determine if the blends are single-... 

The quantity Tg displays positive deviations from additivity, ATg 130 K, which points toward strong interactions between OH groups of EVOH. In terms of the Gordon-Taylor [1952] equation with mass fraction Wi of component i in the copolymer. 

The Gordon-Taylor-Wood (GTW) relationship is a common test for randomness in copolymers This treatment was applied to the present HPAM and copolymer systems as follows (1) a ser-... 

Fig. 6 Gordon-Taylor-Wood relationship for HPAM and AM-co-AA copolymers.

The effects of copolymerization vary from one system to another but a large number of copolymer rubbers obey the Gordon-Taylor relation quite closely. In effect this proposes that the T, of a copolymer can be linearly interpolated from the TgS of the appropriate homopolymers. Butadiene-styrene random copolymers provide a very good fit but in general interactions between the... 

In the Gordon-Taylor equation (4) Tg is the glass temperature of the copolymer or of the miscible polymer blend, respectively, w and Tg. are the weight fractions resp. glass temperatures of the components. K is a model specific parameter, i.e., ifoT = P ... 

M. Gordon (University of Essex) You said your copolymer effect on T agreed with the Gordon-Taylor equation. That equation was derived in 195 without using the notion of free volume it follows from considering ideal mixing of (overall) molar volumes. As the notional way of splitting overall volumes into free and occupied volumes is controversial I wonder if for your theory it is necessary at all. 

Tg values of several important homopolymers are hsted in reference [2], The values were determined on samples of non-crosslinked emulsion polymers. In crosslinked polymers, Tg is shifted to higher temperatures as a result of the restricted chain mobility. A number of approximations for calculating the Tg of copolymers have been proposed in the literature [26], The Gordon-Taylor equation usually produces reliable results ... 

Styrene forms a homopolymer with a of 100.0°C. The rubbery copolymer with butadiene commonly called styrene-butadiene rubber (SBR) has a Tg of -60°C, whereas the copolymer used for coatings has a of 28.0°C. If a copolymer is made with equal weights of butadiene and vinyl acetate (Tg of polyvinylacetate = 28°C), what is expected for this new copolymer Assume the vahdity of the Gordon-Taylor equation with the same k for any pair of monomers as long as monomer 1 is butadiene. SBR is 25.0 wt% styrene copolymer (coatings) is 25.0 wt% butadiene. 

Gordon, M., Taylor, J. S. Ideal copolymers and the second-order transitions of synthetic rubbers in non-crystalline copolymers. J. Appl. Chem, p. 493, 1952... 

Un cas particuli rement interessant de ces modifications de la composition est constitue par la classe des copolym res, lorsque la succession des deux monomferes est distribute au hasard le long de la chaine (random copolymerization). Dans ce cas, T varie d une manitre continue (mais non necessairement monotone) avec la composition (Gordon et Taylor, 1952 Mandelkern et al. 1957 Illers, 1963). 

Crank, J. The Mathematics of Diffusion, 2nd Ed., Clarendon Press, Oxford, 1975. Gordon, M. and Taylor, J.S. Ideal copolymers and second order transitions in synthetic rubbers. I. Non-crystalline polymers, /. Appl. Chem., 2, 493,1952. Karel, M., Anglea, S., Buera, M.P., Karmas, R., Levi, G., Roos, Y. et al. Stability related transitions of amorphous foods, 246. pp. 249,1994. 

Figure 15.4 Glass transition temperatures of emidsion-polynierized styrene-butadiene copolymers of various compositions (Gordon and Taylor [16])...

Gordon M, Taylor JS. Ideal copolymers and the second-order transitions of synthetic rubbers. 

The description of the historic Gordon-T ay lor and Wood equations for the glass transition of solutions and copolymers can be found in Gordon M, Taylor IS (1952) Ideal Copolymers and the Second-order Transitions of Synthetic Rubbers. I. Noncrystalline Copolymers. J Appl Chem 2 493-500 Wood LA (1958) Glass Transition Temperatures of Copolymers. 1 Polymer Sci 28 319-330 for the relationship to the volume changes, see Kovacs AJ (1964) Glass Transition in Amorphous Polymers. Phenomenological Study. Fortschr Hochpolym Forsch 3 394-508. 

Gladden LF, Sederman AJ (2013) Recent advances in flow MRI. J Magn Reson 229 2-11 Gnutzmann T, Kahlau R, Scheifler S, Friedrichs F, Rossler EA, Rademann K, Emmerhng F (2013) Crystal growth rates and molecular dynamics of nifedipine. CrystEngComm 15 4062-4069 Gordon M, Taylor JS (1952) Ideal copolymers and the second-order transitions of synthetic lubbers. I. non-crystaUine copolymers. J Appl Chem 2 493-500... 

A theoretical interpretation of the glass transition temperature of a copolymer is based on the assumption that the transition occurs at a constant fraction of free volume. Gordon and Taylor [9] assume that in an ideal copolymer the partial specific volumes of the two components are constant and equal to the specific volumes of the two homopolymers. The specific volume-temperature coefficients for the two components in the rubbery and glassy states are assumed to remain the same in the copolymer as in the homopolymers, and to be independent of temperature. The glass transition temperature Tg for the copolymer is then given by [10]... 

Gordon M and Taylor J S (1952) Ideal copolymers and the 2 -order transitions of synthetic rubbers. 1. Noncrystalline copolymers, J Appl Chem 2 493-500. 

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