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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.
The phase behavior of polymer solutions is an important property involved in the development and design of most polymer-related processes. Partially miscible polymer solutions often exhibit two solubility boundaries, the upper critical solution temperature (UCST) and the LCST, both of which depend on the molar mass and the pressure. At ...
The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. [2]
Changes in an amorphous polymer may involve other sub-Tg thermal transitions associated with short molecular segments, side-chains and branches. The linearity of the sf-TM curve will be changed by such transitions. Other relaxations may be due to release of internal stress arising from the non-equilibrium state of the glassy amorphous polymer.
Thermogravimetric analysis or thermal gravimetric analysis (TGA) is a method of thermal analysis in which the mass of a sample is measured over time as the temperature changes. . This measurement provides information about physical phenomena, such as phase transitions, absorption, adsorption and desorption; as well as chemical phenomena including chemisorptions, thermal decomposition, and ...
A topology change is possible by transesterification reactions which do not affect the number of links or the (average) functionality of the polymer, meaning that neither the decomposition of polymer linkages nor the decrease of integrity of polymers happens when transesterification reactions take place.
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.
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. It has a low glass-transition temperature of about -43 °C (20 °C). [clarification needed]