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Copolymers, hydrophobic

It was found that in spite of the large excess of modifying amine (N-isopropyl-, -diethyl, -dipropyl, -diisopropyl, -n-hexyl, -cyclohexyl, -n-octyl), the extent of substitution did not exceed 5-10 molar %. For the case of the N-isopropyl derivative, i.e. [poly(AAm-co-NiPAAm)], the authors connected such results with the temperature-induced conformational transformation of partially hydrophobized copolymer acquiring the contracted conformation, "... which made it difficult for N-isopropylamine to react further with the amide groups [22], Unfortunately, no data on the solution behaviour of these interesting copolymers have been reported to date, although there is a high probability that they would demonstrate certain properties of the protein-like macromolecules. At least, in favour of similar supposition is supported by the results of our studies [23] of somewhat different PAAm partially hydrophobized derivative, whose preparation method is depicted in Scheme 3. [Pg.108]

Micelles from Double-Hydrophobic Copolymers in Organic Solvents. . .. 85... [Pg.77]

Methacrylates with pendant oxyethylene units (FM-19) were polymerized in a controlled way with metal catalysts in the bulk or in water. The catalytic systems include a bromide initiator coupled with Ni-2 for n = 2 (bulk, 80 °C)319 and CuCl for n = 7-8.246-320 The latter polymerization proceeded very fast in aqueous media at 20 °C to reach 95% conversion in 30 min and gave very narrow MWDs (MJMn =1.1 — 1.3). The fast reaction is attributed to the formation of a highly active, monomeric copper species com-plexed by the oxyethylene units. A statistical copolymerization of FM-19 (n = 7—8) and FM-20, a methacrylate with a oligo (propylene oxide) pendant group, led to hydrophilic/hydrophobic copolymers with narrow MWDs (MwIMn = 1.2).320... [Pg.484]

The degradation rates for a number of polyanhydrides are available in the literature [1, 82,83], However, recently, a new class of polyanhydrides poly(FAD-SA) have been synthesized from non-linear hydrophobic dimer of oleic acid or erucic acid and relatively hydrophilic sebacic acid. This copolymer can be prepared in various ratios of the monomers to achieve the desired degree of hydrophobicity increasing the percentage of FAD, a more hydrophobic copolymer, is obtained. Another advantage of this copolymer is its ability to be formulated as films, microspheres, and beads [84],... [Pg.129]

The release profiles were also fitted to Eq. (1) using a nonlinear regression program to obtain estimates of B, the erosion rate. R 2 in all cases was greater than 0.99 and hence the good fit of the release profile to Eq. (1). The optimized values of B obtained by nonlinear regression are listed in Table 18. The erosion rate ranged from 0.0037 cm/day for the most hydrophobic copolymer. P(FAD-SA) 80 20 to 0.028 cm/day for the most hydrophilic copolymer, P(FAD-SA) 10 90. However, the erosion rate was not linearly dependent on the hydrophili-city of the polymer, expressed as % of sebacic acid in the copolymer (Fig. 18). [Pg.130]

Horbett, T., M. Schway, and B. Ratner, Hydrophilic-hydrophobic copolymers as cell substrates Effect on 3T3 cell growth rates. Journal of Colloid and Interface Science, 1985, 104, 28-39. [Pg.350]

Figure 1. a. The emission wavelength for the fluorescence of 10 M ANS in solutions of varying concentration of polyacrylamide (PAM) and a polyacrylamide copolymerized with 1 mol % dodecylacrylamide (C12RAM). b. The polarization of fluorescence of 10 M ANS from the same solutions of PAM and the hydrophobic copolymer with dodecylacrylamide. [Pg.428]

The Kinetics of Adsorption of Plasma Proteins to a Hydrophilic-Hydrophobic Copolymers... [Pg.245]

Adsorption of Proteins from Plasma to a Series of Hydrophilic-hydrophobic Copolymers. II. Compositional Analysis with the Prelabeled Protein Technique... [Pg.246]

Hydrophilic-Hydrophobic Copolymers as Cell Substrates Effect on 3T3 Cell Growth Rates... [Pg.251]

Polymersomes generated from simple AB block copolymers display inter-digitated membrane. The robust entanglement within the hydrophobic layer can be considered as a physical cross-link able to enhance the mechanical properties of those aggregates compared to liposomes [5]. Tri-block (BAB) hydrophobic-hydrophilic-hydrophobic copolymers are similar to diblock copolymers since there... [Pg.127]

In this linkages are covalent bonds. They are influenced by the chemical linkages and functional groups present in the gel networks. Hydrophilic polymers and hydrophilic-hydrophobic copolymers are examples of chemically crosslinked gels obtained by the polymerization of vinyl monomers in fhe presence of multifunctional crosslinkers. These crosslinkers are the crosslinking points within and between the polymeric chains allowing modification of the entire physicochemical properties of the gel systems... [Pg.409]

This same synthetic approach was also used to create diamine ROMP monomers. The homopolymers were again selective for S. aureus, but not for E. coli. Since the diamine monomers closely resembled the methyl monomers in terms of hydrophobicity, copolymers of these two monomers were... [Pg.309]

Studies concerning functional surfaces produced by surface segregation of copolymers typically involved the use of either double hydrophobic copolymers [121, 122] or amphiphilic block copolymers [123-126] as additives to be placed at the surface. These copolymers are designed to contain hydrophobic segments... [Pg.123]

Finally, the size of N-tetraalkylammonium counter-ion for PLL solutions is found to play a role similar to that of side-chain length for hydrophobic copolymers of maleic acid and alkylvinyl ethers. [Pg.15]

A similar behaviour is also found here for hydrophilic-hydrophobic copolymers obtained by partial hydrolysis of a polyacrylamide (COP,) [13]. By adjusting the percentage of hydrolysis, the hydrophobic character of chains can be varied and a behaviour from a normal polyelectrolyte to an abnormal one can thus be observed. As illustrated in Figure 3, the compact conformation stable at low a is dependent on the relative proportion of statistically distributed hydrophobic and hydrophilic sequences [18]. The transition region is shifted to higher values of a as the hydrophobic character of the chain increases. [Pg.21]


See other pages where Copolymers, hydrophobic is mentioned: [Pg.228]    [Pg.464]    [Pg.110]    [Pg.728]    [Pg.347]    [Pg.17]    [Pg.70]    [Pg.76]    [Pg.100]    [Pg.36]    [Pg.166]    [Pg.137]    [Pg.422]    [Pg.246]    [Pg.110]    [Pg.593]    [Pg.27]    [Pg.27]    [Pg.29]    [Pg.50]    [Pg.127]    [Pg.70]    [Pg.299]    [Pg.235]    [Pg.237]    [Pg.1611]    [Pg.225]   
See also in sourсe #XX -- [ Pg.593 ]




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Block copolymers, hydrophobic

Block copolymers, hydrophobic associations

Charged Hydrophobic Copolymers

Copolymers hydrophilic-hydrophobic grafts

Copolymers, hydrophobic hydrophilic polymer grafted

Hydrophilic-hydrophobic block copolymers)

Hydrophilic/hydrophobic copolymers adsorption onto

Hydrophilic/hydrophobic copolymers characterization

Hydrophilic/hydrophobic copolymers functionalized

Hydrophilic/hydrophobic copolymers improvement

Hydrophilic/hydrophobic copolymers plasma protein

Hydrophilic/hydrophobic copolymers surface properties

Hydrophilic/hydrophobic copolymers units

Hydrophilicity/hydrophobicity properties block copolymers

Hydrophobic-hydrophilic copolymers

Hydrophobic-polar copolymers

Hydrophobically associating copolymers

Hydrophobically associating copolymers fluorescence

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