Browsing by Author "HORTA, A"
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- ItemASSOCIATION EQUILIBRIA THEORY OF PREFERENTIAL ADSORPTION IN SYSTEMS WITH SOLVENT SOLVENT AND SOLVENT POLYMER INTERACTIONS(1989) HORTA, A; RADIC, D; GARGALLO, L
- ItemDIELECTRIC AND VISCOMETRIC BEHAVIOR OF POLY(DIBENZYL ITACONATE) AS A FUNCTION OF TEMPERATURE(1988) GARGALLO, L; YAZDANIPEDRAM, M; RADIC, D; HERNANDEZFUENTES, I; HORTA, A
- ItemDIPOLE-MOMENT AND CONFORMATIONAL-ANALYSIS OF ITACONATE POLYMERS(1988) SAIZ, E; HORTA, A; GARGALLO, L; HERNANDEZFUENTES, I; RADIC, D
- ItemMICROSTRUCTURE OF ITACONATE POLYMERS CONTAINING BENZYL GROUPS(1987) HORTA, A; HERNANDEZFUENTES, I; GARGALLO, L; RADIC, D
- ItemPARTIAL SPECIFIC VOLUMES OF METHYLSUCCINATES AND POLY(ITACONATE)S(1988) HERNANDEZFUENTES, I; HORTA, A; GARGALLO, L; ABRADELO, C; YAZDANIPEDRAM, M; RADIC, D
- ItemPOLYMERS IN MIXED-SOLVENTS(1992) GARGALLO, L; HORTA, A
- ItemPREFERENTIAL ADSORPTION BEHAVIOR OF POLY(ALKYL METHACRYLATE)S IN 1,4-DIOXANE METHANOL(1985) KATIME, IA; GARGALLO, L; RADIC, D; HORTA, A
- ItemPREFERENTIAL ADSORPTION DETERMINED BY SPECIFIC INTERACTIONS - POLY(DIALKYL ITACONATES) 1,4-DIOXANE/METHANOL(AMER CHEMICAL SOC, 1990) HORTA, A; GARGALLO, L; RADIC, DThe variation of the preferential adsorption coefficient, lambda, with the solvent composition, for a series of poly(dialkyl itaconates) is studied in the mixed solvent 1,4-dioxane/methanol. In these systems specific hydrogen bonding of methanol to 1,4-dioxane and to the polymer take place. Methanol is preferentially adsorbed at low methanol composition, but 1,4-dioxane is preferentially adsorbed at high compositions. All systems here studied show inverstion in lambda. The variation of lambda with solvent composition depends on the size of the side group of the polymer. In order to interpret the influence of hydrogen bonding on these systems, the recent theory of the association equilibria has been applied. According to the results of this theory, the inversion and extrema of lambda come from a balance of effects: the high quality of 1,4-dioxane as solvent and the length of the chains of self-associated methanol, which are complexed with the polymer. It is possible to find a quantitative agreement between this theory and experimental results by using reasonable values for the association constants and interaction parameters of the theory.
- ItemPROPERTIES OF POLY-ELECTROLYTES - POLY(MONO-METHYL ITACONATE) - CONFORMATIONAL AND VISCOMETRIC BEHAVIOR IN DILUTE-SOLUTION(1989) GARGALLO, L; RADIC, D; YAZDANIPEDRAM, M; HORTA, A
- ItemPROPERTIES OF POLYELECTROLYTES .2. POLY(MONOETHYL ITACONATE), CONFORMATIONAL AND VISCOMETRIC BEHAVIOR IN DILUTE-SOLUTION(1993) GARGALLO, L; YAZDANIPEDRAM, M; RADIC, D; HORTA, A; BRAVO, JThe dilute solution behaviour of poly(monoethyl itaconate) (PMEI) has been studied in 2-ethoxyethanol, methanol, dimethylsulfoxide and water, at 298 K, by intrinsic viscosity and light scattering measurements, and size exclusion chromatography (SEC). Weight-average molecular weight was determined in methanol. PMEI shows typical polyelectrolyte behaviour. The Kuhn-Mark-Houwink-Sakurada relationships were established in the media studied. The conformational parameters (sigma and C(infinity)) and the thermodynamic parameter (B) were calculated. The results are compared with previous studies of poly(monomethyl itaconate).
- ItemSIZE-EXCLUSION CHROMATOGRAPHY OF POLY(NORMAL-ALKYL ITACONATE)S - NONEXCLUSION EFFECTS(1992) RADIC, D; GARGALLO, L; LEON, A; HORTA, APoly(n-alkyl itaconates) containing long alkyl side chains (comb polymers) are eluted through PS gel in THF at 298 K. Their retention volumes are higher than those predicted by universal calibration, indicating affinity of the polymers for the gel. The distribution coefficient for solute-gel interactions, Kp(Kp > 1), increases with polymer molecular weight. This increase is larger for the polymer bearing the longest n-alkyl side chain and is scarcely sensitive to the presence or absence of free carboxylic groups in the polymer (monoitaconates). This might be due to a balance of the solute-gel and solute-solvent interactions.
- ItemSYNTHESIS AND SOLUTION PROPERTIES OF COMB-LIKE POLY(MONO-NORMAL-ALKYL-ITACONATES) .2. POLY(MONODODECYL ITACONATE)(1991) LEON, A; GARGALLO, L; RADIC, D; HORTA, AThe monoester of itaconic acid with n-dodecyl alcohol was synthesized and polymerized. Polymer fractions were characterized by viscometry, size exclusion chromatography (s.e.c.) and light scattering. Thermodynamic and dimensional parameters were determined and calculated. The results found are 67 angstrom for the statistical segment length l and 8 angstrom for the chain diameter d. These results are compared with those reported previously for a similar compound.
- ItemSYNTHESIS AND SOLUTION PROPERTIES OF COMBLIKE POLY(MONO-N-ALKYL ITACONATES) .1. POLY(MONODECYL ITACONATE)(1989) LEON, A; GARGALLO, L; HORTA, A; RADIC, D
- ItemSYNTHESIS, DILUTE-SOLUTION PROPERTIES AND CHAIN FLEXIBILITY OF POLY(DIESTERS) OF ITACONIC ACID .2. POLY(METHYL DECYL ITACONATE)(1992) LEON, A; GARGALLO, L; RADIC, D; BRAVO, J; HORTA, AThe diester of itaconic acid with decyl and methyl groups was prepared and polymerized. The dilute solution behaviour of poly(methyl decyl itaconate) poly[1-(decyloxycarbonylmethyl)-1-(methoxycarbonyl)ethylene] (PMeDI) was studied in tetrahydrofuran and 1-butanol at 298 K, by light scattering, size-exclusion chromatography, and viscometric measurements. The empirical Kuhn-Mark-Houwink-Sakurada relationships were established. The molecular parameters were calculated using one theory of the excluded volume.
- ItemSYNTHESIS, SOLUTION PROPERTIES, AND CHAIN FLEXIBILITY OF POLY (METHYL DODECYL ITACONATE)(TAYLOR & FRANCIS INC, 1990) LEON, A; LOPEZ, M; GARGALLO, L; RADIC, D; HORTA, AThe dilute solution behavior of poly(methyl dodecyl itaconate) (PMeDoI) has been studied in THF and n-butanol at 298 K, by intrinsic viscosity, light scattering, and size-exclusion chromatography (SEC) measurements. The Kuhn-Mark-Houwink-Sakurada relationships were established. The flexibility factors sigma and C infinity and the thermodynamic parameters B were calculated using the Stockmayer-Fixman equation. The A2 and the B values are indicative of the presence of the excluded volume effect. The results obtained are compared with those previously found for poly(mono dodecyl itaconate) (PMDoI) and discussed in terms of specific influence of the free carboxylic group in the poly(monoester).
- ItemTHE EFFECT OF SIDE-CHAINS ON THE PARTIAL SPECIFIC VOLUMES OF POLY(ORTHO-ALKYLPHENYL METHACRYLATE)S AND POLYDIITACONATES(1988) GARGALLO, L; RADIC, D; HAMIDI, N; CARDENAS, L; HORTA, A; HERNANDEZFUENTES, I