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Blends Containing Amphiphilic Biopolymers and their Compatibility
Behavior. MINI-REV ORG CHEM 2022. [DOI: 10.2174/1570193x18666210712112453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract:
This mini-review deals with the miscibility behaviour of two biopolymers, chitosan and
alginate. It is well known that the miscibility in multifunctional polymer blends is favoured due to
specific interactions, which origin a negative heat of mixing. Particular interest is focused on functionalized
polymers because they are the most suitable way to obtain interacting polymers, producing
a single-phase material. Due to the polyfunctionality of chitosan (CS) and other biopolymers, they can
be taken into account as a basis of a strongly interacting polymer. They would allow obtaining compatible
polymeric materials. For this reason, blends containing CS with different vinyl polymers have
been studied. The most significant polymeric blends with these natural polymers will be analyzed in
this review. Chitosan is obtained from the biopolymer chitin through sequential processes of demineralization,
deproteinization and deacetylation. The native chitin is obtained by direct separation from
the marine crustaceans shell, which is abundant on the sea coasts. Some classic results that relate to
the polymeric blends containing amphiphilic polymers will be discussed. Another biopolymer of the
coast is Sodium Alginate (SA). Alginate also allows the formation of compatible polymer blends.
Results in this regard will also be analyzed in this review.
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Host-guest interactions of non-steroidal anti-inflammatory drugs on the functionalized dendronized polymeric nanocomposite, Poly(N-tris[((cyano-ethoxy)methyl] methylacrylamide). JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2018. [DOI: 10.1080/10601325.2018.1426389] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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3
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Synthesis, characterization and molecular dynamics simulation of dendronized poly(3,5-diphthalimidoalkylphenyl methacrylate)s. POLIMERY-W 2016. [DOI: 10.14314/polimery.2016.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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4
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Study of the dielectric relaxation of poly(phenylpropyl acrylate) and poly(phenylpropyl methacrylate): effect of slight differences in chemical structure. POLYM INT 2015. [DOI: 10.1002/pi.4973] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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5
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Interactions in blends of dendronized polymeric nanocomposites with some common drugs. J Appl Polym Sci 2015. [DOI: 10.1002/app.42450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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6
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Interaction of dendronized polymeric nanocomposites with isomeric cyclohexanediols. J Appl Polym Sci 2015. [DOI: 10.1002/app.42267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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7
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Amphiphilic 2-ethyl hexyl methacrylate-b-N
,N
′-dimethylacrylamide diblock copolymer monolayer behaviour at the air − water interface†. POLYM INT 2014. [DOI: 10.1002/pi.4845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Synthesis and Characterization of a Branched Poly(Methacrylamide): Thermal Stability and Molecular Simulation Studies of Their Blends With Vinylic Polymers. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2014. [DOI: 10.1080/10601325.2014.953367] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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9
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Polymers containing phtalimidoalkyl groups in the side chains. effect of the alkyl groups in monolayers at the airwater interface. E-POLYMERS 2012. [DOI: 10.1515/epoly.2012.12.1.755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractSurface activity of poly(methacrylate)s containing phthalimidoalkyl groups was studied. Surface pressure-area isotherms ( -A) at the air-water interface were determined. These polymers form stable and condensed monolayers. The monolayers are more condensed and the limiting surface area A0 values decrease when the number of the methylene groups in the lateral chains increases. Surface pressure variation at the semidilute region of the monolayers was expressed in terms of the scaling laws as power function of the surface concentration. The static elasticity εo and the exponent of the excluded volume υ were determined. The hydrophobicity degree of polymers was estimated from the determination of the total surface free energy values by wettability measurements. Molecular dynamic simulation (MDS) was performed in order to explain the experimental behavior of polymers at the air-water interface.
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Study of Miscibility in Polymer Blends Obtained from Binary Inclusion Complexes of γ-Cyclodextrin and Polycarbonate/Poly(Ethylene Terephthalate). J MACROMOL SCI B 2012. [DOI: 10.1080/00222348.2012.662452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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11
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Crystallization behavior of PEO in blends of poly(ethylene oxide)/poly(2-vinyl pyridine)-b
-(ethylene oxide) block copolymer. POLYM ENG SCI 2011. [DOI: 10.1002/pen.22183] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Poly(ester)s containing germanium and silicon in the main chain, part 2: Static and dynamics behavior of monolayers at the air-water interface. J Appl Polym Sci 2011. [DOI: 10.1002/app.33020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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13
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Amphiphilic diblock copolymers containing poly(N-hexylisocyanate): Monolayer behavior at the air-water interface. J Appl Polym Sci 2011. [DOI: 10.1002/app.34078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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Contributions of Dipolar Relaxation Processes and Ionic Transport to the Response of Liquids to Electrical Perturbation Fields. J Phys Chem B 2011; 115:5730-40. [DOI: 10.1021/jp110554h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Synthesis and physicochemical characterization of branched poly(monomethyl itaconate). E-POLYMERS 2010. [DOI: 10.1515/epoly.2010.10.1.1022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe synthesis and characterization of branched polymers derived from poly (monomethyl itaconate) (PMMI) are reported. Important changes in the properties of the functionalized products were found with respect to the base polymer, establishing a close relationship with the hydrophobic/hydrophilic balance of the products. The intrinsic viscosity of the branched PMMI showed an increment in its hydrodynamic volume due to the insertion of branched molecules, which correspond to a first generation of dendrons. Their incorporation into the polymer chain caused a change in the surface energy values of the sample films and enabled the products to form stable monolayers at the air-water interface
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Dipolar and Ionic Relaxations of Polymers Containing Polar Conformationally Versatile Side Chains. Macromolecules 2010. [DOI: 10.1021/ma1004875] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Comparative Study of Thermal Degradation of N-vinylimidazole/Phenoxy- and Methoxyethylmethacrylate Copolymers. INT J POLYM MATER PO 2010. [DOI: 10.1080/00914031003627288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Equilibrium and surface rheology of monolayers of insoluble polycations with side chains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:12561-12568. [PMID: 19689139 DOI: 10.1021/la901762u] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have studied monolayers of poly(n-tetradecyl 4-vinylpyridinium-co-4-vinylpyridine) bromide with different degrees of quaternization at the air-water interface. The isotherms (surface pressure vs area) present several phase transitions: at low monolayer coverage, there is a phase transition over a characteristic area that increases on increasing the quaternization degree. This behavior can be rationalized in terms of a mean-field theory of 2D semiflexible polymeric chains and could be an indication of a disorder-order transition from a 2D isotropic liquid (IL) at low surface concentration to a 2D nematic phase (N) at higher concentrations. Low-frequency oscillatory strain experiments show that at low surface coverage the monolayers exhibit highly nonlinear behavior, even for low strain amplitude, whereas at higher surface coverage the response is linear for strains higher than 20%. In addition, stress relaxation experiments show a minimum in the characteristic times that coincide with the transition area. These unexpected results at low surface coverage might be characteristic of the system or related to the fact that the oscillatory experiments do not strictly correspond to constant surface-coverage conditions. However, they are in agreement with high-frequency viscoelasticity, obtained by surface quasielastic light scattering, that shows that the dilational viscosity is higher at low surface concentration than for concentrations beyond the surface phase transition. At higher coverage, there is a second phase transition, after which the isotherms present hysteresis, which is not observed below. Ellipsometry indicates that, after this transition, the monolayer thicken, which may be related to 3D growth into a multilayer.
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Copolymers of Phenoxyethyl Methacrylate with Butyl Methacrylate: Synthesis, Characterization and Reactivity Ratios. INT J POLYM MATER PO 2009. [DOI: 10.1080/00914030802583759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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23
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Copolymers of Phenoxyethyl Methacrylate with Glycidyl Methacrylate: Synthesis, Characterization and Reactivity Ratios. INT J POLYM MATER PO 2008. [DOI: 10.1080/00914030701413306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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24
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Bio-foam enhances larval retention in a free-spawning marine tunicate. Proc Natl Acad Sci U S A 2007; 104:18120-2. [PMID: 17984045 PMCID: PMC2084306 DOI: 10.1073/pnas.0708233104] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Indexed: 11/18/2022] Open
Abstract
Here we report a mechanism that reduces dispersal of early developing stages and larvae in a free-spawning intertidal and shallow subtidal tunicate, Pyura praeputialis (Heller 1878), in the Bay of Antofagasta, Chile. The spawning of gametes by the tunicate into the naturally turbulent aerated seawater decreases their surface tension and induces the formation of a bio-foam. Water collected from foamy intertidal pools and tide channels showed a high concentration of P. praeputialis early developing stages and tadpole larvae in the foam. Because gametes are synchronically spawned for external fertilization and larvae settle near adults, our results suggest that this bio-foam increases fertilization success and effective settlement of their short-lived larvae in the vicinity of the adults spawning the gametes. This mechanism reinforces published evidence suggesting that local retention of intertidal and inshore marine invertebrate larvae may be more common than previously thought, offering, for instance, new perspectives for the design and networking of marine protected and management areas.
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Blends Containing Amphiphilic Polymers VI. Compatibilization of N-alkylitaconamic acid-co-Styrene Copolymers with Poly(hydroxypropyl methacrylate) and Poly(4-vinylphenol). INT J POLYM MATER PO 2007. [DOI: 10.1080/00914030601100706] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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27
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N-1-ALKYLITACONAMIC ACIDS-CO-STYRENE COPOLYMERS. 1. SYNTHESIS, CHARACTERIZATION AND MONOMER REACTIVITY RATIOS. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2007. [DOI: 10.1081/ma-100101079] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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28
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Poly(ester)s Containing Germanium and Silicon in the Main Chain. 1. Langmuir Monolayer Characterization. J MACROMOL SCI B 2007. [DOI: 10.1080/00222340500407988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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New three-arm amphiphilic and biodegradable block copolymers composed of poly(epsilon-caprolactone) and poly(N-vinyl-2-pyrrolidone). Synthesis, characterization and self-assembly in aqueous solution. J Colloid Interface Sci 2007; 310:136-43. [PMID: 17368468 DOI: 10.1016/j.jcis.2007.01.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Revised: 01/04/2007] [Accepted: 01/06/2007] [Indexed: 11/26/2022]
Abstract
The synthesis, characterization and the self-assembly process of a novel biodegradable block copolymer containing a poly(epsilon-caprolactone), PCL, central block and three poly(N-vinyl-2-pyrrolidone), PVP, arms are reported. Three samples with different amounts of PVP were investigated. The copolymers were characterized by FTIR spectroscopy, (1)H NMR and viscosity measurements. The composition and the molecular weights of the block copolymers were established using size exclusion chromatography SEC and (1)H NMR. Micelle formation by these copolymers was monitored by using the vibrational fine structure of pyrene monomer fluorescence and the critical aggregation concentrations, cac, of the copolymers in aqueous solution were determined using sigmoid Boltzmann-type fitting of the fluorescence data. Dynamic light scattering measurements showed a bimodal size distribution for the copolymers in solution, indicating that the micellization is an intermolecular process. Partitioning coefficients of pyrene between copolymer micelles and water were also determined and increase in magnitude with increasing epsilon-caprolactone content of the copolymer.
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Copolymers of Phenoxyethyl Methacrylate with N‐Vinyl‐2‐pyrrolidone: Synthesis, Characterization and Reactivity Ratios. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2007. [DOI: 10.1080/10601320601044641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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31
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Polymer conformation and viscometric behavior. VIII. solution properties and chain flexibility of cyclic side chain containing poly(monoitaconates). J MACROMOL SCI B 2006. [DOI: 10.1080/00222349408248080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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32
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Dielectric and Mechanical Relaxational Behavior of Poly (Chlorobenzyl Methacrylate)s. INT J POLYM MATER PO 2006. [DOI: 10.1080/00914030600692539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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33
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Blends of Poly(N-vinyl-2-pyrrolidone)/Poly(dialkyl itaconates) and Poly(methacrylates). INT J POLYM MATER PO 2006. [DOI: 10.1080/00914039408038299] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Synthesis, solution properties, and chain flexibility of poly (methyl dodecyl itaconate). J MACROMOL SCI B 2006. [DOI: 10.1080/00222349008230375] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Surface properties of inclusion complexes between α-cyclodextrin and poly(ethylene oxide). J Colloid Interface Sci 2006; 301:607-11. [PMID: 16780856 DOI: 10.1016/j.jcis.2006.05.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 05/09/2006] [Accepted: 05/10/2006] [Indexed: 10/24/2022]
Abstract
The surface properties of the supramolecular inclusion complex (IC) obtained from the threading of alpha-cyclodextrin (alpha-CD) onto poly(ethylene oxide) (PEO) free in solution are studied. The complexes were characterized by IR, (1)H NMR spectroscopy, and thermal analysis. The variation of the interfacial tension, gamma(int), with inclusion complex (IC) concentration and temperature were determined. The results were compared with those found for PEO under the same conditions. alpha-CD does not present surface activity. To quantify the adsorption process of IC and PEO in aqueous medium, the Gibbs equation was used. The driving force for adsorption of IC at the air/aqueous interface seems to arise from an enthalpic contribution. The wettability of the alpha-CD, PEO, and IC films with two liquids was determined by static contact angle measurements. The hydrophobicity degree was estimated. IC is more hydrophobic than PEO and alpha-CD.
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Maleic anhydride-co-stearyl methacrylate copolymers. Synthesis, characterization, and some aspects of the solution behavior. J MACROMOL SCI B 2006. [DOI: 10.1080/00222349808220454] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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COMPATIBILIZATION OF POLY(ETHYLENE OXIDE)/POLY(STYRENE) BLENDS: EFFECT OF THE MOLECULAR WEIGHT OF THE COMPATIBILIZER. J MACROMOL SCI B 2006. [DOI: 10.1081/mb-100107796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Poly(ethylene oxide)s hydrophobically modified. Adsorption and spreading at the air–water interface. J Colloid Interface Sci 2006; 299:70-5. [PMID: 16527292 DOI: 10.1016/j.jcis.2006.01.063] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2005] [Revised: 01/16/2006] [Accepted: 01/29/2006] [Indexed: 10/24/2022]
Abstract
A comparative study of spread and adsorbed monolayer of poly(ethylene oxide)s of different molecular weight hydrophobically modified with alkyl isocyanates of different length chain is reported. The modification of the polymer was carried out according to reported procedures. The polymers obtained were studied at the air-water interface by Langmuir isotherms for spread monolayers and by Gibbs isotherms for the adsorption process. Isotherms obtained are interpreted in terms of the hydrophobic and hydrophilic balance of the polymers. Limiting area per repeating unit (A(0)) and collapse pressure (pi(c)) from spread monolayers were obtained. Spread monolayers of the hydrophobically modified polymers show larger collapse pressure values than unmodified polymer monolayers. In the adsorption process the excess surface concentration Gamma(infinity), area per repeat unit sigma, and efficiency of the adsorption were determined. The values of the area occupied per repeat unit in adsorbed monolayer (sigma) were larger than those of the spread monolayer. The efficiency of the adsorption of poly(ethylene oxide)s increases with the hydrophobic modification and with the alkyl chain length.
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Influence of the Fine Structure on the Response of Polymer Chains to Perturbation Fields. Macromolecules 2006. [DOI: 10.1021/ma052381c] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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[Study of presynaptic nigrostriatal pathway by 123-I-FD-CIT-SPECT (DatSCAN SPECT) in primary orthostatic tremor]. Neurologia 2006; 21:37-9. [PMID: 16525925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023] Open
Abstract
INTRODUCTION Primary orthostatic tremor (OT) is defined as a clinical syndrome with high frequency (13-18 Hz) tremor when standing predominantly involving legs and trunk. OT is thought to be driven by an unique supraspinal tremor generator. Previous studies suggest that the nigrostriatal dopaminergic transmission is impaired in patients with OT. CLINICAL CASE All three patients at an age of 56, 45 and 72 years fulfilled the diagnosis criteria of primary OT. The duration of illness amounted to 4, 3 and 1 year, respectively. The three patients had single-photon emission computed tomography (SPECT) using 123-I-FP-CIT as dopamine transporter tracer (DatSCAN). RESULTS DatSCAN was normal in every patient. CONCLUSIONS OT is considered to be caused by a central oscillator because high-frequency tremor bursts are time locked in arm, leg, trunk, and even facial muscles and peripheral stimulation does not reset the tremor. Some reports suggest that the central generator may be located in the posterior fossa. In our patients presynaptic nigrostriatal pathway was normal.
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Blends containing amphiphilic polymers. V. Compatibilization ofN-alkylitaconamic acid-co-styrene copolymers with interacting polymers. J Appl Polym Sci 2006. [DOI: 10.1002/app.24652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Poly(tetrahydropyranyl-2-methyl methacrylate): Comparative study in solution and at the air/water interface. J Colloid Interface Sci 2005; 292:397-402. [PMID: 16083897 DOI: 10.1016/j.jcis.2005.05.089] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2005] [Revised: 05/27/2005] [Accepted: 05/31/2005] [Indexed: 11/17/2022]
Abstract
In this work a comparative study of different molecular-weight fractions of the amphiphilic polymer poly(tetrahydropyranyl-2-methyl methacrylate) (PTHPMM) in solution and at the air/water interface is reported. The synthesis of the polymer was carried out in solution by radical polymerization. The polymer was fractionated and five fractions were studied in solution and at the air/water interface. The weight-average molecular weight M(w), the second virial coefficient A(2), and the radius of gyration R(g) were determined in toluene by static light scattering. Intrinsic viscosities [eta] of the polymer fractions in three solvents were obtained. The Kuhn-Mark-Houwink-Sakurada relationships were established. The Langmuir isotherms for different polymer fractions were obtained at the air/water interface by monolayer compression at constant temperature. The overlap surface concentrations were determined, and from these results the radius of gyration in two dimensions was calculated. The thermodynamic power of the toluene and the air/water interface for PTHPMM were estimated from the empirical relationship between the radius of gyration in two and three dimensions and the weight-average molecular weight.
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Specific interactions in blends containing Chitosan and functionalized polymers. Molecular dynamics simulations. POLYMER 2005. [DOI: 10.1016/j.polymer.2005.08.059] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Deconvolution of the relaxations associated with local and segmental motions in poly(methacrylate)s containing dichlorinated benzyl moieties in the ester residue. J Chem Phys 2005; 123:114904. [PMID: 16392594 DOI: 10.1063/1.2013252] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The relaxation behavior of poly(2,3-dichlorobenzyl methacrylate) is studied by broadband dielectric spectroscopy in the frequency range of 10(-1)-10(9) Hz and temperature interval of 303-423 K. The isotherms representing the dielectric loss of the glassy polymer in the frequency domain present a single absorption, called beta process. At temperatures close to Tg, the dynamical alpha relaxation already overlaps with the beta process, the degree of overlapping increasing with temperature. The deconvolution of the alpha and beta relaxations is facilitated using the retardation spectra calculated from the isotherms utilizing linear programming regularization parameter techniques. The temperature dependence of the beta relaxation presents a crossover associated with a change in activation energy of the local processes. The distance between the alpha and beta peaks, expressed as log(fmax;beta/fmax;alpha) where fmax is the frequency at the peak maximum, follows Arrhenius behavior in the temperature range of 310-384 K. Above 384 K, the distance between the peaks remains nearly constant and, as a result, the a onset temperature exhibited for many polymers is not reached in this system. The fraction of relaxation carried out through the alpha process, without beta assistance, is larger than 60% in the temperature range of 310-384 K where the so-called Williams ansatz holds.
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Comparative study of poly(2,3 and 4 methyl cyclohexyl methacrylate)s. Dielectric relaxation spectroscopy (DRS). POLYMER 2005. [DOI: 10.1016/j.polymer.2005.06.109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Interfacial Properties of Poly(Caprolactone) and Derivatives. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2004. [DOI: 10.1081/ma-120030926] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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