ten Brinke, G.; Ruokolainen, J.; Ikkala, O.; Torkkeli, M.; Serimaa, R.ABSTRACT: The solid state of comb copolymer-like systems obtained by blending poly(4-vinylpyridine) with pentadecylphenol was studied by a combination of techniques. Depending on the amount of pentadecylphenol, several regimes are present. For 0.5 e x e 1.0 (x is the ratio between the number of phenol and pyridine groups) the alkyl tails form an interdigitated hexagonally packed crystalline layer. Small-angle X-ray scattering measurements show that for x ) 1.5 and 2.0 the excess pentadecylphenol cocrystallizes with the associated pentadecylphenol, with the free phenol groups probably aggregating near the middle of the crystalline layer. For x g 2.0 the orthorhombic crystal modification also appears. Finally for x g 3.0, part of the excess pentadecylphenol macrophase separates on crystallization, forming an additional phase of pure pentadecylphenol with the familiar orthorhombic packing. These findings are similar to results obtained for real comb copolymer systems, i.e., containing covalently bonded side chains. However, our systems are essentially different due to the dynamic hydrogen-bonding equilibrium, which implies that the equilibrium solid state may always involve some form of macrophase separation.

The average size and shape of a polymer coil confined in a slit between two parallel plates depends on the distance L between the plates. On the basis of numerical results, four different regimes can be distinguished. For large values of L the coil is essentially unconfined. For intermediate values the coil orientates without being squeezed considerably. For still smaller values the coil is squeezed with a corresponding decrease in the value of the radius of gyration. A further reduction in slit width is accompanied by a sharp increase in the value of the radius of gyration, signaling the onset of the transition from threeto two-dimensional behavior. ¿-Dependent scaling relations are supposed to be valid in the latter regime. Using Monte Carlo results for self-avoiding walks on a cubic lattice, scaling predictions for the parallel component of the radius of gyration and the end-to-end point distance as well as for the osmotic pressure and the number of segments at the wall are presented and verified.

Ordering in supramolecular elastomer-amphiphile systems. 4. Vinylpyridine-divinylbenzene networks with alkylphenols Luyten, M.C; Alberda van Ekenstein, G.O.R.; Wildeman, J.; ten Brinke, G.; Ruokolainen, J.; Ikkala, O.; Torkkeli, M.; Serimaa, R. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. FIN-00014, Helsinki, Finland Received June 4, 1998; Revised Manuscript Received September 28, 1998 ABSTRACT: We report here on the extension to elastomers of the idea of inducing nanoscale ordering in supramolecular polymer systems based on the principle of hydrogen bonding between amphiphiles and (block co-)polymers. Three different networks have been synthesized using 4-vinylpyridine and divinylbenzene (0.5, 1.0, and 2.0 mol %, respectively) and are further complexed with pentadecylphenol or nonadecylphenol. For low degrees of cross-linking (0.5 and 1.0 mol % divinylbenzene), mesomorphic structures are formed, and order-disorder transitions are observed by small-angle X-ray scattering (SAXS) and differential scanning calorimetry. For the highest degree of cross-linking (2.0 mol % divinylbenzene), mesomorphic structures is no longer observed. The presence of ordered lamellar structures is confirmed by transmission electron microscopy (TEM). SAXS and TEM clearly reveal the deteriorating effect of an increasing degree of cross-linking on the structure formation.

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