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Polymer morphology is a microscale property that is largely dictated by the amorphous or crystalline portions of the polymer chains and their influence on each other. Microscopy techniques are especially useful in determining these microscale properties, as the domains created by the polymer morphology are large enough to be viewed using modern ...
Polymers contain different morphologies on the molecular level which give rise to their macro properties. Long range disorder in the polymer chain is representative of amorphous solids, and the chain segments are considered amorphous. Long range polymer order is similar to crystalline material, and chain segments are considered crystalline.
Polymers are composed of long molecular chains which form irregular, entangled coils in the melt. Some polymers retain such a disordered structure upon freezing and readily convert into amorphous solids. In other polymers, the chains rearrange upon freezing and form partly ordered regions with a typical size of the order 1 micrometer. [3]
Polyamorphism is the ability of a substance to exist in several different amorphous modifications. It is analogous to the polymorphism of crystalline materials. Many amorphous substances can exist with different amorphous characteristics (e.g. polymers).
In polymer physics, spherulites (from Greek sphaira = ball and lithos = stone) are spherical semicrystalline regions inside non-branched linear polymers. Their formation is associated with crystallization of polymers from the melt and is controlled by several parameters such as the number of nucleation sites, structure of the polymer molecules, cooling rate, etc. Depending on those parameters ...
Polymers that are formed by free-radical mechanisms such as polyvinyl chloride are usually atactic. [citation needed] Due to their random nature atactic polymers are usually amorphous. [citation needed] In hemi-isotactic macromolecules every other repeat unit has a random substituent. [citation needed]
Disordered polymers: In the solid state, atactic polymers, polymers with a high degree of branching and random copolymers form amorphous (i.e. glassy structures). [45] In melt and solution, polymers tend to form a constantly changing "statistical cluster", see freely-jointed-chain model .
Solvent vapor annealing (SVA) is a widely used technique for controlling the morphology and ordering of block copolymer (BCP) films. [1] [2] [3] By controlling the block ratio (f = NA/N), spheres, cylinders, gyroids, and lamellae structures can be generated by forming a swollen and mobile layer of thin-film from added solvent vapor to facilitate the self-assembly of the polymer blocks. [4]