Intermacromolecular complexes

Philippova and Starodubtzev have also extensively studied the complex-ation behavior of polyacids and PEG, especially, the system of crosslinked of poly(methacrylic acid) and linear poly(ethylene glycol) (Philippova and Starodubtzev, 1995 Philippova et al., 1994). They observed that decreasing the molecular weight of PEG from 6000 to 1500 resulted in its slower diffusion into the swollen network of PMAA, and a drastic decrease in both the stability and equilibrium composition of the intermacromolecular complex. Analysis of dried polymer networks of PMAA with absorbed PEG chains by FT-IR spectroscopy revealed the presence of two types of hydrogen bonded structures (1) dimers of methacrylic acid at absorption frequency of 1700 cm-1 and (2) interpolymer complexes of PMAA and PEG at 1733 cm-1. In addition, they also suggested as a result of their studies, that the hydrogen bonded dimer of PMAA forms preferentially to the intermacromolecular complex between the PMAA network and PEG chains. 

In these aggregation phenomena, the formation of intermacromolecular complexes is attributed to the fact that macromolecules with complementary binding sites interact with each other almost stoichiometrically in solution due to certain secondary binding forces. In this review, the formation of complementary complexes in synthetic macromolecular systems is mainly discussed. 

Secondary Binding Forces Between Intermacromolecular Complexes... 

Intermacromolecular complexes are divided into the following four classes on the basis of the main interaction forces. However, it should be noted that this classification is only made for simplicity. 

Table 3. Formation of intermacromolecular complexes between synthetic macromolecules...

Only few theoretical studies on the formation of such intermacromolecular complexes have been performed up to now. This may be due to the following facts... 

Table 3 summarizes typical intermacromolecular complexes composed of synthetic macromolecules. A review of the formation of intermacromolecular complexes composed of copolymers has been published by Bekturov et al.387). 

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