摘要:
A process for producing laminates which contain at least one centrally arranged, ion-conductive membrane which is, at least over a substantial part of its two mutually opposite flat faces, electrically conductively bonded to at least one catalytically active substance and to at least one two-dimensional, gas-permeable, electron-conductive contacting material, the bonding of at least two of the said components having been effected by lamination. The process comprises carrying out the bonding of the ion-conductive membrane, of the catalytically active substance and of the electron-conductive contacting material continuously. The ion-conductive membrane is brought together with at least the electron-conductive contacting material in the exact position by means of transport and feeding devices and the two components are laminated and bonded to one another by pressing them together. The range of variation in the a.c. resistances of the laminates produced by the process according to the invention is ±10%. The laminates are particularly suitable for use in fuel cells or electrolysers.
摘要:
A sulfonated aromatic polyether ketone of the formula (II) [Ar—O—Ar′—CO—Ar′—O—Ar—CO—Ar″—CO—] (II) in which from 1% to 100% of the O-phenylene-CO units are substituted with an SO3M group and sulfonated and unsulfonated O-phenylene-CO units can be in any desired sequence with respect to one another, the radicals Ar, Ar′ and Ar″ independently of one another are substituted or unsubstituted 1,2-, 1,3- or 1,4-phenylene rings, and M, taking into account the ionic valencies, comprises one or more elements selected from the following group: H, NR4+, where R is H or C1-C4-alkyl, or an alkali metal or alkaline earth metal or a metal from subgroup 8, and is preferably H, NR4+, Li, Na, K, Ca, Mg, Fe or Pt.
摘要:
A sulfonated aromatic polyether ketone of the formula (II) [Ar—O—Ar′—CO—Ar′—O—Ar—CO—Ar″—CO—] (II) in which from 1% to 100% of the O-phenylene-CO units are substituted with an SO3M group and sulfonated and unsulfonated O-phenylene-CO units can be in any desired sequence with respect to one another, the radicals Ar, Ar′ and Ar″ independently of one another are substituted or unsubstituted 1,2-, 1,3- or 1,4-phenylene rings, and M, taking into account the ionic valencies, comprises one or more elements selected from the following group: H, NR4+, where R is H or C1-C4-alkyl, or an alkali metal or alkaline earth metal or a metal from subgroup 8, and is preferably H, NR4+, Li, Na, K, Ca, Mg, Fe or Pt.
摘要:
Laser-markable molding compositions, molding produced therewith and method of marking the same, wherein the molding compositions comprise: (a) at least one semicrystalline thermoplastic; and (b) at least one particulate additive selected from the group consisting of (i) light-sensitive salt compounds, (ii) inorganic oxides having an average particle diameter of less than 250 nm, and combinations thereof; wherein the light-sensitive salt compounds comprise compounds having two or more captions, wherein at least one of the two or more captions is selected from the group consisting of Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Ag, Sn, Sb, La, Pr, Ta, W, and Ce; and wherein at least another of the two or more captions is selected from the group consisting of elements of periods 3-6 of main groups II and III, elements of periods 5-6 of main group IV, elements of periods 4-5 of transition groups III-VIII, and the lanthanoids.
摘要:
The present invention relates to novel molding compositions based on semicrystalline engineering thermoplastics which, in conventional processing techniques, give moldings with reduced surface gloss. A feature of the molding compositions is that they comprise, in a polymer matrix, if appropriate with the usual additives, polymer particles with a median size d50 of from 0.1 μm to 100 μm, and comprise at least one other incompatible or semicompatible polymer which has not been chemically crosslinked, and also, if appropriate, comprise salt-like additives.The invention further relates to moldings which are produced by means of conventional processing techniques, in particular via injection molding, from these matt-effect molding compositions.
摘要:
A process and an apparatus are described for preparation of oxymethylene polymers. This process encompasses polymerization, in a homogeneous phase, of a monomer which forms oxymethylene groups, as far as 90% of maximum conversion in the presence of an acetal of formaldehyde and of an initiator for cationic polymerization, followed by deactivation of the reaction mixture. The resultant oxymethylene polymers have alkyl ether end groups and are extremely stable.
摘要:
The present invention relates to novel molding compositions based on semicrystalline engineering thermoplastics which, in conventional processing techniques, give moldings with reduced surface gloss. A feature of the molding compositions is that they comprise, in a polymer matrix, if appropriate with the usual additives, polymer particles with a median size d50 of from 0.1 μm to 100 μm, and comprise at least one other incompatible or semicompatible polymer which has not been chemically crosslinked, and also, if appropriate, comprise salt-like additives. The invention further relates to moldings which are produced by means of conventional processing techniques, in particular via injection molding, from these matt-effect molding compositions.
摘要:
Novel halogen-free flame-retardant thermoplastic molding compositions are described, and give laser-markable moldings with increased quality of marking. The molding compositions comprise at least one thermoplastic A) and at least one light-sensitive compound of salt type B1) which within the polymer matrix when exposed to laser light changes its color or leads to a change in the color of the polymer matrix, and/or at least one light-sensitive or light-sensitizing oxide B2) which within the polymer matrix when exposed to laser light changes its color or leads to a change in the color of the polymer matrix, and at least one halogen-free compound or mixture C) which has a positive effect on the flammability and fire performance of the molding composition, and if appropriate, other conventional additives D).The invention further relates to moldings produced from these laser-markable flame-retardant molding compositions, and also to laser-marked moldings produced therefrom. A process for laser marking is also disclosed, as is the use of the laser-markable, flame-retardant molding compositions for production of laser-marked moldings.
摘要:
An apparatus is described for preparation of oxymethylene homo- and copolymers. This encompasses heterogeneous polymerization of a monomer which forms oxymethylene groups in the presence of an acetal of formaldehyde and of an initiator for cationic polymerization, followed by the deactivation of the polymer in a homogeneous phase via treatment with a basic aprotic solvent or with an aprotic solvent which comprises a base. Oxymethylene homopolymers with very high stability are also described.
摘要:
The present invention relates to novel molding compositions based on semicrystalline engineering thermoplastics which, in conventional processing techniques, give moldings with reduced surface gloss. A feature of the molding compositions is that they comprise, in a polymer matrix, if appropriate with the usual additives, polymer particles with a median size d50 of from 0.1 μm to 100 μm, and comprise at least one other incompatible or semicompatible polymer which has not been chemically crosslinked, and also, if appropriate, comprise salt-like additives. The invention further relates to moldings which are produced by means of conventional processing techniques, in particular via injection molding, from these matt-effect molding compositions.