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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]
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 ...
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 ...
, 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 ...
Additionally, it can be shown that for a binary blend of polymer species with equal chain lengths (=) the critical concentration should be = /; however, polymers blends have been observed where this parameter is highly asymmetric. In certain blends, mixing entropy can dominate over monomer interaction.
Alpha-olefins such as 1-hexene may be used as co-monomers to give an alkyl branched polymer (see chemical structure below), although 1-decene is most commonly used for lubricant base stocks. [8] 1-hexene, an example of an alpha-olefin. Many poly-alpha-olefins have flexible alkyl branching groups on every other carbon of their polymer backbone ...
Polymer chemistry is a sub-discipline of chemistry that focuses on the structures, chemical synthesis, and chemical and physical properties of polymers and macromolecules. The principles and methods used within polymer chemistry are also applicable through a wide range of other chemistry sub-disciplines like organic chemistry , analytical ...
Graft copolymers are a branched copolymer where the components of the side chain are structurally different than that of the main chain. Graft copolymers containing a larger quantity of side chains are capable of wormlike conformation, compact molecular dimension, and notable chain end effects due to their confined and tight fit structures. [1]