copolymer glass transition temperature
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How to increase the glass transition temperature of binary copolymers
Can you tell me specifically which binary copolymer it is?
Should we increase the content of rigid links and reduce the content of flexible links? It seems like a very simple question. The teacher seemed to have mentioned it when I was in school. Why can’t I remember anything now?
Generally, the content of the second order is adjusted. . . It also depends on what the copolymerized monomers are. .
The problem with adjusting the formula of two monomers is that this question is too broad. . .
Is there such a phenomenon that the glass transition temperature of the copolymer is lower or higher than the glass transition temperature of any comonomer during homopolymerization? :L
Tg is mainly determined by intermolecular force, stiffness. If hydrogen bonds can be introduced, Tg can be increased. In addition, benzene rings or branches can be introduced, which reduces the relative rotation between bonds, increases stiffness, and increases Tg.
There is a calculation company, maybe 1/TG temperature of copolymer = 1/comonomer 1+1/comonomer 2+. . . . . Is that how it’s calculated? I don’t know if that’s right. :lol I hope you have some reference. Then increase the TG temperature and strengthen the content of rigid chains, which should be correct.
It should be the Fox formula: 1/Tg=∑wi/Tg(i)] , where ∑wi=1. For binary copolymers, 1/Tg=w1/Tg1+w2/Tg2, w1+w2=1. Generally, the Tg of the binary copolymer will be between the Tg of the two copolymers, and the DSC curve of the copolymer sometimes has only one Tg, and sometimes there are 2 Tg.
Generally, the greater the rigidity of the molecular chain, the higher the glass transition temperature. If you choose strong binary comonomers for copolymerization, the glass transition temperature will naturally be higher.
Can you talk about the effect of glass transition temperature on processing performance?
The glass transition temperature is the highest temperature used for plastics and the lowest temperature used for rubber. The higher the temperature, the higher the temperature required for processing. The glass transition temperature is related to the degree of crystallization of the polymer.