Interpolymer interactions

Most of the studies in aqueous solution have been devoted to interactions between homopolymers (5-10. In these systems the mean stoichiometry between interactive groups is close to 1 1. Only a few studies have been devoted to the behaviour of homopolymer/copolymer systems (11-14. Still a variation in copolymer composition leads to a modulation in the interpolymer interaction system. In a sense, inactive groups behave as structure defects. 

Molecular Recognition in Interpolymer Interactions and Matrix Polymerization... 

The Selectivity of Interpolymer Interactions with Regard to Chain Lenghts. 

Some of the above examples show interpolymer interactions to be highly selective — recognition may require, however, insignificant differences in the copolymer com-... 

According to Table 1, the greater part of experimental work was devoted to particular cases of selectivity of interpolymer interactions with regard to chemical structure (reactions of substitution). From the viewpoint of a theoretical description of such reactions, two cases should be distinguished polymer—two oligomers systems and oligomer—two polymers systems. 

We have confined this review only to interpolymer interactions although it is obvious that a number of theoretical conclusions concerning such interactions, are, at least qualitatively, applicable to interactions of macromolecules with the surface of different types of particles. 

It is much simpler to calculate an interpolymer interaction which is sufficiently well modelled by adsorption of chains on a one-dimensional lattice, than to calculate adsorption on the two-dimentional one as well as to calculate adsorption of small particles on the macromolecule. When calculating adsorption on the two-dimensional lattice (usual surface), for example, difficulties rapidly pile up with increasing the degree of filling of the surface with macromolecules it is difficult to take into consideration self- and intercrossings of the adsorbed macromolecules, the influence exerted by the length and rigidity of these macromolecules, etc. 

Interbiopolymer complexes are formed in aqueous media between oppositely charged biopolymers, when the attractive forces between non-identical macromolecules are larger than between macromolecules of the same type. Interbiopolymer complexes can be both soluble (system 1) and insoluble (system 2). It has been shown that nonspecific interpolymer interactions can be reversible and non-reversible and cooperative and noncooperative in nature (Tolstoguzov et al. 1985). 

The formation of a photo-reversible gel is explained as foUows. The azobenzene groups in the surface region of the polymer coil help the coil overlap. When they change to a more polar cis form, the interactions are strengthened. The change in the interpolymer interactions is responsible for the change in the gel melting temperature. 

Interestingly, the lipopolymers exhibit two different diffusion regimes, labeled as Regions I and II. In Region I, in the case of weak interpolymer interactions, D is independent of A, but the plateau or Region I value depends on the number of polymeric units, N. In Region II, D scales proportionally with A, and is also dependent on N. 

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