Coupling agent modification silane

Other strategies for improving clay exfoliation in rigid PU foams include the addition of coupling agents, mainly silane-based (Han et al., 2008 Kim et al., 2008), or processing modifications, in addition to the already mentioned ultrasounds, such as microwave processing (Lorenzetti et al., 2010). 

Analog-to-glass fibers silanes are used as coupling agents for natural fiber polymer composites. For example, the treatment of wood fibers with product A-175 improves wood dimensional stability [53]. In contrast, a decrease of mechanical properties was observed for coir-UP composites after a fiber modification with di-chloromethylvinyl silane [54]. The treatment of mercer-... 

Many other functional silane coupling agents are available from commercial suppliers, including hydroxyl, aldehyde, acrylate and methacrylate, and anhydride compounds. Substrate modification procedures similar to those discussed above can be used with these reagents to link a biomolecule to an inorganic surface or particle. 

One conventional procedure for organic modification of inorganic particles is to utilize the reaction of the hydroxyl group with silane coupling agents. Many kinds... 

Scheme 12.1.1 Surface modification with silane coupling agent.

Scheme 12.1.5 Modification of colloidal silica ultrafine particles with polymeric silane coupling agents in low polar solvent.

A recent study by DePalma and Tillman [ 10] also demonstrates the potential of surface modification by self-assembled monolayers of low surface energy fiuoroalkyl-containing silanes. Fatty acids, amines and alcohols have long been known to adsorb as monomolecular films on metals. Silane coupling agents have featured strongly in new studies to develop more robust films, covalently bound together and to the metal substrate. 

Several modifications of commercial silane coupling agents have been evaluated to search for improved bonding at the interface. These approaches attempt to use modifiers to counteract basic faults of the individual silanes. Some of these modifications include increased hydrophobic character, increased crosslinking of the siloxane structure, increased thermal stability, and ionomer bond formation to reduce shear degradation at the interface. 

This modification is connected with a reversed use of the silane (siloxane) coupling agents. On the other hand, the hydrosilylation reaction is commonly applied as a method of crosslinking organic polymers containing vinyl and allyl groups with siloxanes and polysiloxanes with Si-H functionality (e. g., [27]). 

We have shown that chemical modification of metal oxide supports, such as silica (SiOz) and TiOz, with silane-coupling agents (organosilanes) having amino groups was effective for dispersion of a catalytic material such as phosphododecatungstate and... 

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