Abstract: A dental material is described which is characterized by a content of silicic acid condensates of norbornene or mercapto silanes, and which, after thiol-ene polymerisation with suitable reactants, shows only slight polymerisation shrinkage and produces polymerisates with high mechanical strength.

Abstract: The invention relates to a self-curing, photochemically or thermally curable resinous dental composition based on polymerisable polysiloxanes, to a process for its preparation and to its use for the preparation of pasty, self-curing, photochemically or thermally curable dental materials. Said composition is obtainable by hydrolytic condensation of one or more hydrolytically condensable silicon compounds, 1 to 100 mol %, based on monomeric compounds, of silanes of the general formula: Y.sub.n- SiX.sub.m R.sub.4-(n+m) and/or {X.sub.n R.sub.k Si?R.sup.2 (A).sub.l !.sub.4-(n+k) }.sub.x B being selected. The radicals A, X, Y, R.sup.2, R' and R are identical or different and have the following meaning: A=O, S, PR', POR', NHC(O)O or NHC(O)ONR', B=a straight-chain or branched organic radical which is derived from a compound B' having at least one (for l=1 and A=NHC(O)O or NHC(O)NR') or at least two C.dbd.C double bonds and 5 to 50 carbon atoms, R=alkyl, alkenyl, aryl, alkylaryl or arylalkyl, R'=H, alkyl or aryl, R.

Abstract: The invention relates to hydrolyzable and polyadditive silanes, a method of heir production and of their use in the production of (hetero) silicic acid polycondensates and of polyadducts. The silanes in accordance with the invention have the general formula?(HS--R.sup.5).sub.n R.sup.6 --S--E--R.sup.5 !.sub.a SiX.sub.x R.sup.3.sub.4-a-x (I)in which the groups and indices are equal or different and have the following meaning:E=--CO--NH--, CS--NH--, --CH.sub.2 --CH.sub.2 -- or --CH.sub.2 --CH(OH)--;R.sup.3 =alkyl, alkenyl, aryl, alkylaryl or arylalkyl each with 1 to 15 carbon atoms, whereby these groups may be interrupted by oxygen or sulfur atoms, by ester, carbonyl, amide or amino groups;R.sup.5 =Alkene, arylene, arylenealkene or arylenealkene each with 1 to 15 carbon atoms, whereby these groups may be interrupted by oxygen or sulfur atoms, by ester, carbonyl, amide or amino groups;R.sup.

Abstract: The hydrolyzable and polymerizable silanes have the formula I, ##STR1## wherein X is hydrogen, a halogen, a hydroxy, an alkoxy group, an acyloxy group, an alkylcarbonyl group, an alkoxycarbonyl group or --NR.sup.2.sub.2 group; wherein R.sup.

Abstract: The invention includes hydrolyzable and polymerizable silanes, methods of making them and using them to obtain silicic acid(hetero)polycondensates and silicic acid(hetero)polymerizates. The hydrolyzable and polymerizable silanes have the formula I, ##STR1## wherein A=O, S, NH or C(O)O;whereinB=a straight chain or branched organic residue with at least one C.dbd.C double bond and from 4 to 50 carbon atoms;R is an alkyl group, alkenyl group, aryl group, alkylaryl group or an arylalkyl group;R' is a substituted or unsubstituted alkylene group, arylene group, arylenealkylene group or alkylenearylene group each having zero to ten carbon atoms, with the proviso that the substituted groups each have at least one oxygen atom, sulfur atom and/or amine group substituent;R.sup.

Abstract: The invention relates to self-curing systems based on polymerizable and hydrolytically condensable or condensed silicon compounds. The systems according to the invention comprise one or more components which contain starter and/or activator systems, at least one component of the system containing a silicon compound of the formula I or Ia, or a precondensed form thereof,{X.sub.a R.sub.b Si?R'(A).sub.c !.sub.(4-a-b) }.sub.x B (I){X.sub.a R.sub.b Si?(R'A).sub.c !.sub.(4-a-b) }.sub.x B (Ia)The invention furthermore relates to activators in the form of silane-bonded tertiary amines of the general formula IX or X.

Abstract: Silanes of the general formula (I):{X.sub.a R.sub.b Si(R'(A).sub.c).sub.(4-a-b) }.sub.x B (I)in which the groups and indices have the following meaning:X: hydrogen, halogen, hydroxy, alkoxy, acyloxy, alkyl carbonyl, alkoxycaryl or --NR".sub.2 ;R: alkyl, alkenyl, aryl, alkaryl, or aralkyl;R': alkylene, arylene or alkylene arylene;R": hydrogen, alkyl or aryl;A: O, S, PR", POR", NHC(O)O or NHC(O)NR";B: straight chain or branched organic group, which is derived from a B' compound with at least one C.dbd.C double bond for c.dbd.1 and A.dbd.NHC(O)O or NHC(O)NR") or at least two C.dbd.C double bonds, and 5 to 50 carbon atoms;a: 1, 2 or 3;b: 0, 1 or 2;c: 0 or 1;x: whole number, whose maximum value corresponds to the number of double bonds in compound B' minus 1, or is equal to the number of double bonds in compound B', when c.dbd.

Abstract: Hydrolyzable and polymerizable silanes for producing poly (hetero) condensation products and (hetero) polymers, the silanes having the general formula (I)Y.sub.n Si X.sub.m R.sub.4-(n+m) (I),wherein the residues X, Y and R may be the same or different and are defined as follows:R=alkyl, alkenyl, aryl, alkylaryl or arylalkyl,X=hydrogen, halogen, hydroxyl, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR'.sub.2, with R'=hydrogen, alkyl or aryl,Y=a substituent containing a substituted or unsubstituted 1,4,6 -trioxaspiro-[4,4]-nonane residue,n=1, 2 or 3, m=1, 2 or 3, with n+m.ltoreq.4.The silanes of the present invention are processed to form scratch-resistant coatings, filling, adhesive or sealing compounds, molded articles or embedding media.

Abstract: Silanes of the general formula (I):{(X.sub.a R.sub.b Si(R'(A).sub.c).sub.(4-a-b) }.sub.x B (I)in which the groups and indices have the following meaning:X: hydrogen, halogen, hydroxy, alkoxy, acyloxy, alkyl carbonyl, alkoxycaryl or --NR".sub.2 ;R: alkyl, alkenyl, aryl, alkaryl, or aralkyl;R': alkylene, arylene or alkylene arylene;R": hydrogen, alkyl or aryl;A: O, S, PR", POR", NHC(O)O or NHC(O)NR";B: straight chain or branched organic group, which is derived from a B' compound with at least one C.dbd.C double bond for c=1 and A=NHC(O)O or NHC(O)NR") or at least two C.dbd.C double bonds, and 5 to 50 carbon atoms;a: 1, 2 or 3;b: 0, 1 or 2;c: 0 or 1;x: whole number, whose maximum value corresponds to the number of double bonds in compound B' minus 1, or is equal to the number of double bonds in compound B', when c=1 and A stands for NHC(O)O or NHC(O)NR";are suitable to prepare homo and copolycondensates and homo or copolymers according to the sol-gel method or by photochemical or thermal polymerization.

Abstract: Polycondensates modified with unsaturated organic groups on the basis of rolytically condensable compounds of silicon and optionally other elements from the group B, Al, P, Sn, Pb, the transition metals, the lanthanides and the actinides, in which 5 to 100 mole %, based on the monomer compounds, of the fundamental hydrolytically condensable compounds are selected from silanes of the general formula (I):{X.sub.a R.sub.b Si(R'(A.sub.c).sub.(4-a-b) }.sub.x B (I)in which the groups and indices have the following meaning:X: hydrogen, halogen, hydroxy, alkoxyl acyloxy, alkyl carbonyl, alkoxycarbonyl or -NR".sub.2 ;R: alkyl, alkenyl, aryl, alkaryl, or aralkyl;R': alkylene, arylene or alkylene arylene;R": hydrogen, alkyl or aryl;A: O, S, PR", POR", NHC(O)O or NHC(O)NR";B: straight chain or branched organic group, which is derived from a compound B' with at least one C.dbd.C double bond (for c=I and A=NHC(O)O or NHC(O)NR"), or at least two C.dbd.

Abstract: A process is described for coating electrically conducting substrates with n insulating coating, which comprises first subjecting silicon compounds which both have groups susceptible to hydrolysis and also contain (organic) radicals accessible to a polymerization to a polycondensation, then depositing the resulting polycondensate on the subtrate and curing the coating so obtained by polymerization involving the organic radicals. If the polycondensate additionally contains groups which are capable of carrying a charge, coating by electrophoretic dip coating is possible.

Abstract: Cyclohexane derivatives of the formula IR.sup.1 --A.sup.1 --Z.sup.1 --A.sup.2 --R.sup.2 IwhereinR.sup.1 and R.sup.2 are each H or an alkyl group which has 1-10 C atoms and in which one or two non-adjacent CH.sub.2 groups can also be replaced by 0 atoms and/or --CO-groups, and/or --CO--O-- groups and/or --CH.dbd.CH-- groups, or are F, Cl, Br, CN or R.sup.3 --A.sup.3 --Z.sup.2 --,A.sup.1 is --A--, A.sup.4 --Z.sup.o --A-- or --A--Z.sup.o --A.sup.4 --,A is a trans-1,4-cyclohexylene or 1,4-cyclohexenylene group which is unsubstituted or is monosubstituted or polysubstituted in the 2-, 3-, 5- and/or 6-position by F and/or Cl and/or Br and/or CN and/or an alkyl group or a fluorinated alkyl group each of which has 1-10 C atoms and in which one or two non-adjacent CH.sub.2 groups can also be replaced by 0 atoms and/or --CO-- groups and/or --CO--O-- groups, which trans-1,4-cyclohexylene or 1,4-cyclohexenylene group can optionally also be substituted in the 1-position and/or 4-position and one or two CH.sub.

Abstract: Liquid-crystalline tercyclohexyls of the formula ##STR1## in which R is an alkyl group with 1-12 C atoms, in which one or two non-adjacent CH.sub.2 groups can be replaced by 0,X is --CN, --COOR.sup.1, --OOCR.sup.1, --COR.sup.1 or R.sup.1, andR.sup.1 is an alkyl group having 1-12 C atoms, with the proviso that in the case where X=R.sup.1 at least one CH.sub.2 group in the alkyl group R is replaced by 0, and useful in liquid-crystalline dielectrics.