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The Flory–Fox equation relates the number-average molecular weight, M n, to the glass transition temperature, T g, as shown below: =, where T g,∞ is the maximum glass transition temperature that can be achieved at a theoretical infinite molecular weight and K is an empirical parameter that is related to the free volume present in the polymer sample.
In the case of polymers, conformational changes of segments, typically consisting of 10–20 main-chain atoms, become infinitely slow below the glass transition temperature. In a partially crystalline polymer the glass transition occurs only in the amorphous parts of the material. The definition is different from that in ref. [9]
TPU is a block copolymer consisting of alternating sequences of hard and soft segments or domains formed by the reaction of (1) diisocyanates with short-chain diols (so-called chain extenders) and (2) diisocyanates with long-chain diols. By varying the ratio, structure and/or molecular weight of the reaction compounds, an enormous variety of ...
Mixture of polymers and solvent on a lattice. Flory–Huggins solution theory is a lattice model of the thermodynamics of polymer solutions which takes account of the great dissimilarity in molecular sizes in adapting the usual expression for the entropy of mixing.
PTMC is a predominantly amorphous polymer in the relaxed state but it can present some crystallinity, particularly when the chains are stretched. [ 4 ] The polymer presents glass transition temperature ( T g {\displaystyle T_{g}} ) between -15 and -30 °C and melting temperature ( T m {\displaystyle T_{m}} ) ranging from 38 to 41°C.
Polyetherketoneketone (PEKK) is a semi-crystalline thermoplastic in the polyaryletherketone (PAEK) family of polymers. It possesses high heat, chemical, and mechanical load resistance. [1] PEKK has a glass transition temperature (Tg) of 162 °C. [2] HDD part made from Polyetherketoneketone
Poly(butyl acrylate) (PBA) is a family of organic polymers with the formula (CH 2 CHCO 2 CH 2 CH 2 CH 2 CH 3) n. It is a synthetic acrylate polymer derived from butyl acrylate monomer. The polymers are colorless. This homopolymer is far less important than copolymers derived from methyl acrylate and other monomers.
Non-linear polymers and copolymers, and polymer assemblies are named using the italicized qualifiers in Table 2. [5] The qualifier, such as branch, is used as a prefix (P) when naming a (co)polymer, or as a connective (C), e.g., comb, between two polymer names.