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miscible polymer blends (homogeneous polymer blends): Polymer blend that is a single-phase structure. In this case, one glass transition temperature will be observed. The use of the term polymer alloy for a polymer blend is discouraged, as the former term includes multiphase copolymers but excludes incompatible polymer blends. [3]
In polymer chemistry, compatibilization is the addition of a substance to an immiscible blend of polymers that will increase their stability. Polymer blends are typically described by coarse, unstable phase morphologies; this results in poor mechanical properties. Compatibilizing the system will make a more stable and better blended phase ...
block copolymer: A copolymer that is a block polymer. In the constituent macromolecules of a block copolymer , adjacent blocks are constitutionally different, i.e. adjacent blocks comprise constitutional unit derived from different species of monomer or from the same species of monomer but with a different composition or sequence distribution ...
, where ΔS is the change in entropy of mixing, R is the gas constant, Φ is the volume fraction of each polymer, and x is the number of segments of each polymer. [3] x 1 and x 2 increase with higher degrees of polymerization and thus molecular weight. Since most useful polymers are high in molecular weight, the change in entropy experienced ...
One well-studied [4] [6] effect on interaction energies neglected by unmodified Flory–Huggins theory is chain correlation. In dilute polymer mixtures, where chains are well separated, intramolecular forces between monomers of the polymer chain dominate and drive demixing leading to regions where polymer concentration is high.
Poly(p-phenylene oxide) (PPO), poly(p-phenylene ether) (PPE), poly(oxy-2,6-dimethyl-1,4-phenylene), often referred to simply as polyphenylene oxide, is a high-temperature thermoplastic with the general formula (C 8 H 8 O) n. It is rarely used in its pure form due to difficulties in processing.
A more efficient analysis of copolymer molecular mass and composition is possible using GPC combined with a triple-detection system comprising multi-angle light scattering, UV absorption and differential refractometry, if the copolymer is composed of two base polymers that provide different responses to UV and/or refractive index. [4]
A polymer is a substance composed of macromolecules. The latter usually have a range of molar masses (unit g mol −1), the distributions of which are indicated by dispersity (Đ). It is defined as the ratio of the mass-average molar mass (M m) to the number-average molar mass (M n) i.e. Đ = M m /M n. [4]