Crosslinking silane

Fig. 2. Relaxation modulus G(t) of a set of polydimethylsiloxane samples with increasing extent of crosslinking plotted against time of crosslinking. The linear PDMS chains (Mn 10 000, polydis-persity index 2) were endlinked with a four-functional silane crosslinker catalyzed by a platinum compound. Samples with different extent of reaction were prepared by poisoning the reaction at different times. The actual extent of reaction was not determined. Two of the samples are clearly before the gel point (LST) and two beyond. The third sample is very close to the gel point. Data of Chambon and Winter [5] evaluated by Baumgartel and Winter [8]...

Fig. 26. Tan 3 of a crosslinking PBD (Mw = 18 000) as a function of reaction time [31]. Parameter is the frequency co. The polymer is vulcanized at the pendant vinyl units with a bifunctional silane crosslinker using a platinum compound as catalyst. The curves intersect at the gel point resulting in...

Gravesend, 2002, pp.2. 30cms. 25/4/2002 CATAPYRRIC SX545 CM540U SILANE CROSSLINKABLE LOW-SMOKE LOW-TOXICITY HALOGEN-FREE FLAME-RETARDANT COMPOUND, FOR INSULATION OF LV CABLES AND SHEATHING OF ALL TYPES OF CABLES AEI Compounds Ltd. 

Figure 4.6 Illustration of a covalent organic framework (COF) material composed of hexahydroxytriphenylene and either tetra(4-dihydroxyborylphenyl)methane or silane crosslinking moieties. (From Reference [56] with permission.)...

On the other hand, the alkoxide system presented several problems in formulation. The system first chosen as a model consisted of a trimethoxymethyl silane crosslinker, 8000 centistoke HEB siloxane, and a catalyst. A number of catalysts were used and each exhibited different cure rates and electrical properties. DuPont tetraalkoxytitante-Tyzor appears to he one of the better catalysts used in this type of curing system. Fillers are usually incorporated into the silicone formulation to improve mechanical properties, promote adhesion, and to serve as light screening and pigment agents. Cab-o-sil, a form of fumed silica, carbon-black, titanium dioxide and calcium carbonate are then used as RTV fillers. 

Silane Crosslinking. Further, silane crosslinked UHMWPE has been used for acetabular cups for total hip replacements in goats. In this case, the number of in vivo debris particles appeared to be greater for crosslinked materials than conventional UHMWPE (29). 

Keywords Adhesion silane composites hydrophobic silane crosslinked silane ionomer bonding. 

Chemical Nature Silane crosslinker Active Materials, percent 100... 

Keywords silane, crosslinking, hydrolysis, coating latex, adhesion promoter... 

It is clear that the shoulders visible in Fig. 2 have markedly increased in intensity relative to the large peak. This indicates that there has been significant ftuther silane crosslinking during the cure of the drawn-down film. Again, physical evidence of crosslinking such as increased gel content and solvent double rub resistance are also seen (see Appendix for typical performance characteristics). 

Silanes have been used in sealants since the early 1960s when they were introduced successfully in polysulfide formulations. It was found that only small amounts of silane were needed in the formulation to improve adhesion to surfaces such as glass, metals, and, in some cases, concrete without using a primer. More recently, hybrid sealants (made of an organic polymer backbone and a silane crosslinker) have been widely commercialized. Many of these hybrid sealants have superior properties and will bond to a variety of substrates. 

Silane-Crosslinking High-Performance Spray Foams... 

Summary As all conventional spray foams contain monomeric isocyanates, they can present toxicological hazards. Therefore, an isocyanate-ftee substitute for these foams has been developed. This isocyanate-free foam is cured by a crosslinking reaction of silane-terminated prepolymers (STPs). This silane crosslinking system exhibits some new properties, and several problems occur that are completely unknown with ordinary isocyanate spray foams. In particular, crack formation during foam curing turns out to be a crucial problem. Therefore it was necessary to develop modified STPs and to use special STP-propellant mixtures. 

Scheme 2. Curing reaction of silane crosslinking foams (STP-foams).

The silane crosslinker contains a wide range of reactive substituents e.g. amino-, carboxy-, carbonamido-, oxime-, carbonyl- and/or alkoxy-groups. 

Key words Silanization, Crosslinking, Biomolecules, Immunoassay, Array, Detection, Biosensor. 

Abstract. The design and synthesis of new molecular synthons for vapor-phase self-assembled nanodieletrics and silane crosslinkers for crosslinked polymer blend dielectrics is described. These dielectric films exhibit excellent dielectric properties with tunable thicknesses and capacitance values. These new gate dielectric materials are integrated into thin-film transistors based both p- and n-type organic semiconductors. 

CPB Materials. Various types of silane crosslinkers were employed to fabricate crosslinked polymer blend (CPB) dielectrics in this study (Fig. 4). The reactivity of each crosslinker was tested via in situ NMR kinetic studies. The CPB dielectrics were fabricated on various substrates using mixture of polymer and crosslinker solution via spin-coating and gravure-printing. Organic semiconductors and source/ drain electrodes were vacuum-deposited to complete the OFET device. Dielectric and OFET properties were measured under vacuum and ambient as described previously. 

Fig. 4. Schematic of top-contact/bottom-gate OFET device and structures of the CPB precursors (polymer and silane crosslinkers) employed in this study.

M. Bengtsson and K. Oksman. One-step process of silane crosslinked polyethylene/wood flour composites. In Eighth International Conference on Woodfiber-Plastic Composites, Madison, WI, May 23-25, 2005. 

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