Functional chemical fibres with hybrid polymers

New chemical coatings can assist the combination of several features providing durable effects. Specialised surface coatings extend the application fields of base materials. These include the organic-inorganic hybrid polymers ORMOCERe**, the registered trade mark of Fraunhofer-Gesellschaft zur Forderung der angwandten Forschung e.V., Munich. Their structure and new applications are explained, and the hybrid polymers material class discussed. Resistance to scratch, abrasion or rubbing of clear layers obtained is the main feature of this class of materials. Anti-adhesion layers can be introduced to render the coated surface easier to clean. Antistatic layers can also be applied and the results noted. Barrier layers can resist steam and oxygen, particularly used in the packaging industry. Anti-aromatic barriers and anti-migration barriers are also possible, and there is further explanation of these. The coating of natural materials such as leather is covered with seven adv antages, which can be achieved. ORMOCERe class materials can combine various characteristics through their hybrid structure

Special polysiloxanes on glass surfaces

Organically modified siloxanes or silicates are hybrid materials which intrinsically combine properties and functions of inorganic materials, for instance glass, with those of organic polymers. The basic building blocks that make up this class of materials are mainly silicon compounds with a variety of substituents. An inorganic -Si-O-Si-backbone is first constructed by means of hydrolysis and condensation, e.g. of alkoxy groups (sol-gel processing). The inorganic content of the resulting materal can be considerably increased by the addition of alkoxy compounds of aluminium, titanium or zirconium, prior to hydrolysis. Residual non-reactive organic moieties which are stable against hydrolysis such as amino, alkyl or phenyl groups may act as network modifiers, whereas reactive epoxy, vinyl or methacryl groups permit additional organic crosslinking by well known polymerization reactions. The chemical character of these hybrid hydroxy or alkoxy groups, which may react with surface silano

Mehrschichtiger Lackauftrag mit gradierenden Eigenschaften fuer flexible Substrate

EP 1352936 A UPAB: 20040218 NOVELTY - A flexible substrate (I) comprises a coating (II) having graded properties and consisting of at least a base layer and a covering layer whereby both layers are prepared by means of hydrolysable and condensable silanes such that the base layer is more flexible than the covering layer while the covering layer has greater abrasion resistance than the base layer. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a process for the coating of the substrate (I) with a coating (II) comprising application of a base layer onto the substrate, prepared by hydrolytic condensation of at least one silane of formula (1) in the presence of at least one silicon free compound that has at least 4C atoms when the coating does not contain a compound of formula (1) having an R group; application of a covering layer prepared by hydrolytic condensation of at least one silane of formula (2) as well as optionally a hydrolysable and co-condensable metal compound of formula (3) without addition of a pure organic compound; and, drying and/or hardening of the base and the covering layers. (2) a kit comprising a silane of formula (1), a silane of formula (2) and optionally a metal compound of formula (3). RaR'bSiX4 - a - b (1) RxaRybSiX4 - a - b (2) M(OR)x (3) R' = at least 4C alkyl or alkenyl group; R1 = R1, R2 or R3; R1 = at least 4C alkyl; R2 = NR4R5; R3 = organic polymerizable group ;that is bonded to the Si atom by a carbon atom; R4 = H or 1-4C alkyl; R5 = 1-8C alkylene; X = leaving group that preferably under hydrolytic conditions enables the formation of Si-O-Si groups; a = 0-2; b = 1-2; a+b = 1-3; Rx = 1-10C alkyl or alkenyl; Ry = R3; M = 3- or 4-valent metal that is complexable by alcoholate groups; OR = alcoholate groups, preferably methoxy or ethoxy; x = 3 or 4 USE - The flexible substrate (I) is useful for the production of clothing, bags, furniture leather. ADVANTAGE - The substrate (I) has improved water and abrasion resistance

Functional barrier coatings on the basis of hybrid polymers

With barrier coating materials, namely, hybrid polymers (ORMOCER®), it is possible to obtain excellent barrier properties against oxygen, water vapor, and flavor permeation. These hybrid polymers can be synthesized by the sol-gel technique. If extremely low permeation values are needed, the combination of hybrid polymer coatings with thin inorganic oxidic layers (e.g., SiOx, AlOx) is very effective. These passive barrier layers can be further improved by the combination with active barrier layers, e.g., oxygen scavenger layers. The development of novel biodegradable polymer coatings (bioORMOCER®) was achieved by replacing the nonbiodegradable organic components with biodegradable components. The materials can be equipped with additional functions (e.g., antimicrobial, UV-protection properties) and can even be used successfully on the most difficult surfaces to be coated (fluoropolymer-based materials and polyolefins) as adhesion promoters and surface planarization lay ers. This approach makes these functional coating materials promising candidates for special applications in the food packaging industry as well as for sophisticated applications in technical areas: the encapsulation of sensitive organic devices like solar cells, organic light-emitting diodes, or polymer electronic systems. Promising formulations and methods for quality assurance in production processes have already been developed