摘要:
The invention relates to novel polymers or oligomers containing at least sulfinate groups (P—(SO2)nX, X=1-(n=1), 2-(n=2) or 3-(n=3) valent metal cation or H+ or ammonium ion NR4+ where R=alkyl, aryl, H), which are obtained by completely or partially reducing polymers or oligomers containing at least SO2Y-groups (Y═F, Cl, Br, I, OR, NR2 (R=alkyl and/or aryl and/or H), N-imidazolyl, N-pyrazolyl) by means of suitable reducing agents in a suspension or in a solution form.Polymer and polymer(blend)membranes which are obtained by further reacting the received sulfinated polymers, especially by alkylation of the sulfinate groups with mono- di- or oligo functional electrophiles. The invention further relates to methods for producing the sulfinated polymers and for further reacting the sulfinated polymers with electrophiles by S-alkylation.
摘要:
This invention provides a highly porous crosslinked functionalised polymer having interconnected cavities of micron dimensions and having a pore volume greater than about 5.6 cc/g and having a capacity to absorb water and also to absorb saline solutions. The polymers are generally based on styrene or various acrylates or mixtures and have a functional group selected from a large range of ionic and polar compositions.
摘要:
A coating composition comprises: a fluoro-aliphatic group-containing copolymer comprising a repeating unit A corresponding to a fluoro-aliphatic group-containing monomer, and a repeating unit B corresponding to at least one monomer, wherein each of the I/O values of said at least one monomer constituting the repeating unit B is 1.0 or less.
摘要:
An olefinic thermoplastic elastomer composition which includes an acrylic-modified polytetrafluoroethylene. When foamed, such compositions produce a very soft foam with improved processing properties and physical characteristics. A process of foaming and foamed articles are also disclosed.
摘要:
A rubber composition is disclosed containing an ethylene-propylene-nonconjugated diene copolymer rubber (or a blend of an ethylene-propylene-nonconjugated diene copolymer rubber and a diene rubber), a specific alkoxysilane compound, and amorphous silica powder having a specific surface area of 50 to 100 m2/g (BET adsorption). The vulcanized rubber is prepared by vulcanizing such a rubber composition. The rubber composition is excellent in dynamic characteristics and also in mechanical characteristics, dynamic fatigue resistance and thermal aging resistance. It also can provide a vulcanized rubber having the above-mentioned effects.
摘要:
A method is provided for obtaining crosslinked polymers having pendent sulfonic acid groups by crosslinking through the sulfonic acid groups or their precursors with aromatic crosslinkers or aromatic pendent crosslinking groups to form aromatic sulfones. Such crosslinked polymers may be used to make polymer electrolyte membranes (PEM's) that may be used in electrolytic cells such as fuel cells.
摘要:
A rotating stirring device, particularly for mixing heterogeneous systems in mechanical stirred reactors, is fit to be joined to a drive shaft coaxial with respect to the device rotation axis. The device includes a plurality of extended and substantially C-shaped stirring elements symmetrically arranged with respect to the rotation axis and joined to each other at respective ends corresponding with the rotation axis. Such a device permits a very efficient material exchange among different phases to be obtained and to remain substantially constant with an increase in the volume of the mass being stirred. The device is also characterized by a high mixing homogeneity and particularly low shear stress values.
摘要:
Certain ethylenically unsaturated polymerizable monomers having a reactive carboxy group are useful for preparing homo- and copolymers for a variety of uses, including diagnostic assays. The polymers can be supplied as latex particles in aqueous compositions. The monomers are represented by the structure: ##STR1## wherein: R is hydrogen, halo or alkyl of 1 to 3 carbon atoms,M is hydrogen, an alkali metal ion or an ammonium ion, andL is a linking group having from 8 to 50 atoms in its linking chain, and comprises two or more divalent hydrocarbon groups connected or terminated with one or more nitrogen, oxygen or sulfur atoms, or with one or more groups containing such atoms in the linking chains, provided L has at least one arylene which is not directly connected to the terminal ##STR2## group, and further provided that none of the hydrocarbon groups has non-aromatic unsaturated.
摘要:
The present invention is a method to manufacture one or more shaped foam article. Specifically, the present invention is a method of extruding a thermoplastic polymer with a blowing agent to form a foam polymer plank having a density gradient. Preferably, shaped articles are prepared from the surface of the foam plank having the lowest density. The article is shaped by a mold comprising one or a plurality of cavities wherein the periphery of each cavity is defined by a trimming rib, said mold concurrently shapes the foam article and trims the resulting shaped foam article from the surrounding continuous unshaped foam plank. Preferably, the foam has a vertical compressive balance (Rv) equal to or greater than 0.4 and more preferably, the foam has a cell gas pressure less than 1 atmosphere and/or an open cell content of equal to or less than 20 percent.