Silane epoxysilanes

Enamines. In the presence of alumina (Woelm 200 neutral) cw-a,p-epoxy-silanes can be opened by pyrrolidine or morpholine to give a-amino-p-hydroxy-silanes, from which the pure as-enamine can be obtained by KH-induced syn p-elimination (equation I). The isomeric trans-a,p-epoxysilane is inert to this ring... 

Fig. 5. Ionic silane surfactants based upon epoxysilanes...

Fig. 3. v(CH) range of different epoxysilanes SA-layers on silica (absorbance given in Kubelka-Munk units) (A) pure silane (B) silane in H2O (C) silane in toluene. 

Fused silica flour is produced Irom electrically fused Si02 by iron free grinding followed by air separation. As an option, it may be coated with silane. Quarzwerke GmbH treats flour with amino and epoxysilanes. Denki Kagaku Kogyo Co., Ltd. manufactures spherical grades of fused amorphous silica. 

Tremin 283 - grades 010,100,400,600,800 (the higher the number the smaller the particle size) with different silane coating (AST - aminosilane, EST - epoxysilane, MST - methacrylsilane,... 

Reaction of a, fi-epoxy silanes with organocuprates. Hudrlik et al have shown that the reaction of di-n-propylcopperlithium with o , 3-epoxysilanes is both regio- and stereospecific. Thus the cii-epoxide (1) is converted into the erythro-alcohol (2), whereas the franr-epoxide (3) is converted into the threo-alcohol (4). ... 

Some specific organofunctional silanes can be analyzed via colorimetry with suitable reagents. Examples include epoxysilane with bromothymol blue/thiosulfate solution methacryloxy andvinylsUanes with permanganate salts amino/diamino silanes with ninhydrine [33]. The results are semiquantitative within the same system of mineral and silane in all other cases, they are only of qualitative nature. 

Organofunctional epoxysilanes may be prepared by hydrosilylating unsaturated epoxides or epoxidized unsaturated silanes. The hydrosilylation of allyl ethers CH2=CHCH20R is commonly used for synthesis (e.g., y-glycidoxytrimethoxysilane) as follows ... 

Thermoplastic polyester resins, such as PET and PBT, can contain residual phenolic or carboxylic reactive sites that make epoxysilanes effective. Octyl and phenyl silanes can also he used in combination with organofunctional silanes for thermoset applications to improve dispersion of the resin by matching solubility parameters, increase hydrophobic character, and give greater resistance to the attack of water in the interphase region. Aromatic structures in silane... 

For resin systems other than epoxy, or for other epoxy requirements, the glass weavers sometimes apply aminosilanes, epoxysilanes, and chloropropyl-silanes. 

An example of the benefits of silane when used as a primer is shown in Table 25.15 where urethane and epoxy paints were applied to aluminum surfaces using epoxysilane and aminosilane adhesion promoters to improve adhesion. The effects of degreasing and sandblasting the surface were compared to adhesion with the silanes alone [20]. 

Scheme 2.120. The Peterson elimination of jS-hydroxyalkyl-silanes generated by ring opening of a,jS-epoxysilanes.

---