Hydrophobically hydrophilically modified

M. I. Khoma. Composition of foam-extinguishing agent for drilling solutions—contains waste from production of hydrophilic and hydrophobic aerosil, modified with bifunctional silico-organic compound and diesel oil. Patent SU 1795977-A, 1993. 

Low generations of hydrophobic ally modified PAMAM dendrhners also exhibit a tendency to deform at air-water interfaces in order to present the hydrophilic dendrimer interior toward water and the aliphatic chains toward the air (Sayed-Sweet et al. 1997). Similarly, the tendency of poly(aryl ether) dendrhners with peripheral carbox-ylate end groups to aggregate in aqueous media decreased with increasing generation (Fig. 11.16 Laufersweiler et al. 2001). 

However, transfer of the monolayers to solid substrates was inefficient because of the small size of the hydrophilic anchor, which imparted a hydrophobic/hydrophilic imbalance. Accordingly, increasing the size of the hydrophilic anchor facilitated the formation of stable Langmuir films that could be transferred to sohd substrates with a transfer ratio of 1 (Nierengarten et al. 2001). Bayer s research group reported a related approach in which the fullerene was modified with carboxylate-terminated dendrons and alkyl chains (Maierhofer et al. 2000). This amphiphilic fullerene derivative formed stable monolayers that could be compressed and expanded without hysteresis (Fig. 11.46d Maierhofer et al. 2000). 

The Rh(II)-catalysed intramolecular C-H insertion of diazoacetamide in water has been studied.49 This study assessed the factors governing the preferential intramolecular C-H insertion versus O-H insertion with the solvent. The hydrophobic/hydrophilic nature of the amide substituent appeared to be the most significant contribution driving the reaction towards C-H insertion. The nature of the rhodium catalyst precursor also modifies the reaction outcome [Rh2(OAc)4 enhancing the O-H insertion],... 

The rate enhancement of the polymer over that of simple pyridoxamine was a steep function of the length of the alkyl chains added, in polymers with roughly the same percentage of alkylation and of pyridoxamine attachment. At pH 7.0 and 30 °C, the acceleration over the rate with pyridoxamine was 160 for C-l chains, 180 for C-3, 500 for C-6, 1000 for C-9, 2300 for C-12, and 2500 for the C-15 and C-18 normal alkyl chains. This chain effect seems unlikely to involve hydrophobic binding of a substrate as hydrophilic as pyruvic acid. Instead the hydrophobic chains modify the pK,s of the amino groups in the polymer and also create a cavity in which the transamination can take place in a less than fully aqueous environment. 

This led to the inclusion of two types of particles into the emulsions and the formation of multiple emulsions. For example, hydrophobically modified particles were dispersed in toluene, while hydrophilically modified particles were dispersed in water. Emulsification of this system produced water-in-toluene-in-water or toluene-in-water-in-toluene multiple emulsions. Formulations of one type over the other were achieved... 

Functional properties of some enzymatically modified and EPM-treated products of milk proteins [136] were determined as follows. An enzymatically prehydrolyzed commercial milk protein concentrate (SR) without further hydrolysis, and casein hydrolyzed by alcalase, a-chymotrypsin, and papain, respectively, were used as substrates in the EPM reaction. The concentration of the hydrolysates was 20% w/ v in the EPM reactions. A methionine methyl ester hydrochloride/ substrate ratio of 1 5 was used for incorporating this amino acid. After incubation, the products with methionine incorporation were simultaneously dialyzed for 2 days through a cellophane membrane against distilled water. The nondialyzable fractions and the EPM products without amino acid enrichment were freeze-dried. Covalent methionine incorporation in the EPM products with amino acid enrichment was verified by exopeptidase hydrolysis of the protein chains. The functional properties of the different EPM products are summarized in Table 1. An important functional property of proteins and/or peptide mixtures is their emulsifying behavior. This is highly influenced by the molecular structure, the position and ratio of hydrophobic-hydrophilic amino acids. Emulsion activity was found to be low (34.0) for casein, and the values determined for enzyme hydrolyzed and modified products were in general even lower. The papain hydrolysate, sample H3, showed here a different behavior as well this was the one of the sample series that had the highest EAI value (43.0). The emulsion stability of the enzymatically modified products displayed tendencies quite opposite to the values of emul-... 

Surface properties of nanoparticles and the character of the polymer matrix determine their interactions and contribute to overall change in conductivity. Lower compatibility of nanoparticles and polymer matrix results in a disorder increase lower crystallinity of the matrix and vice versa, as Lopez et al. (2010) found in nanocomposites of methacrylates to which silica nanoparticles were added. Hydrophobic, (dimethyldichlorosilane)-modified nanosilica produced greater changes in dielectric relaxations than umnodified, hydrophilic silica that was more compatible with the polar polymer matrix. Radiochemical changes in nanoparticles like anion formation in nanotitania... 

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