Physically cross-linked polymers

The structure of these gel-like systems of micelles is very different from that of conventional electrophoresis media made from chemically and physically cross-linked polymers of polyacrylamide and agarose [75], The absence of chemical or physical cross-links in the Pluronic gel-like phases may allow a larger degree of freedom for macromolecular transport around the obstacles that make up the medium than occurs in conventional electrophoresis media. 

Gel—A chemically or physically cross-linked polymer that is highly swollen with solvent. Called a hydrogel if the solvent is water (e.g., gelatin). 

Figure 19 Gelled SPE model-top chemically and bottom physically cross-linked polymer. (Reprinted from Ref 220. 2000, with permission from Elsevier)...

JLnterpenetrating polymer networks (IPNs) are a special class of polymer blends in which the polymers exist in networks that are formed when at least one of the polymers is synthesized or cross-linked in the presence of the other. Classical or true IPNs are based solely on thermosetting polymers that form chemical cross-links. More recently, two classes of thermoplastic IPNs have been developed. Apparent IPNs are based on combinations of physically cross-linked polymers. Semi-IPNs are based on combinations of... 

It is well known that thermoset polymers such as epoxy, vinyl ester, polyester, phenolic, etc., are chemically or physically cross-linked polymers (chemical bonds between polymer chains, intermolecular van der Waals bonds, dipole-dipole interactions, and molecular entanglement). These cross-links serve as molecular anchorages, which prevent molecular motion of the... 

Although attempts have been made to investigate the morphological stracture of T -SMPUs, by smdying phase composition and microdomain sizes (the latter defining the physically cross-linked polymer netwoifcs), the structure has not yet been demonstrated systematically (Takahashi et al, 1996 Lin and Chen, 1998a,b Lee et al., 2001). 

Veenstra H, van Dam J, de Boer AP. On the coarsening of co-continuous morphologies in polymer blends Effect of interfacial tension, viscosity and physical cross-links. Polymer 2000 41(8) 3037-3045. 

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