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Flexible, self-extinguishing silicone foams (SFs) with a relatively low density (0.25-0.45 g/cm 3 ) were obtained from a mixture of a,x-(dihydroxy)polydimethylsiloxanes, water, flame retardants (melamine and/or expanded graphite), and polyisocyanates [poly(diphenylmethane isocyanate)]. These compositions were crosslinked at room temperature with branched polymethylhydrosiloxanes with the structure (MeSiO 1.5 ) 3 (MeHSiO) 102 (Me 3 SiO 0.5 ) 5 in the presence of tin octoate as a catalyst. The SFs were modified by the addition of linear or graft carbofunctional polysiloxanes containing chydroxypropyl groups. Only the SFs prepared by means of a dehydrocondensation reaction had a good homogeneity of pores, whereas the foams formed with two kinds of blowing agents (hydrogen and carbon dioxide, generated in the reaction of water with isocyanate groups) had lower densities but a poor homogeneity of pores. Unmodified SFs showed a tensile strength of 20 kPa or less, whereas the foams formed with the addition of poly(diphenylmethane isocyanate) and water had a tensile strength of 23-25 kPa. The SFs with 15 and 30% contents of melamine or expanded graphite had tensile strengths in the ranges 38-45 and 51-54 kPa, respectively. All of the prepared SFs were combustible materials. The SFs without the addition of flame retardants had a limiting oxygen index of approximately 21%, whereas the SFs with a 30% content of fire retardant had self-extinguishing properties and a limited oxygen index of 41-43%.

New mercaptan-terminated polythiourethanes were synthesized from low-molecular-weight dimercaptan oligomers and diisocyanates. The characteristic bands in the FT-IR spectra, and the specific peaks in the 1 H-NMR spectra correlate rather well with the proposed structures of these polymers. Chemical analysis of the epoxy group conversion and swelling measurements were conducted in order to determine the crosslink densities of the cured epoxy resins. The curing characteristics and thermal behaviour of the formulated curing mixtures indicate that the epoxy/polythiourethane stoichiometry and thermal history during cure may greatly affect the curing mechanism and final properties of the epoxy networks. Mechanical studies indicated that the application of polythiourethane hardeners improves the flexibility with increasing tensile strength and impact toughness. The prepared polythiourethane hardeners have an acceptable odour and give a perfectly homogeneous system with the epoxy resins and have good storage stability with other coreactants such as diamines.

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Streszczenie-Na podstawie danych literaturowych przedstawiono ogóln¹ charakterystykê oerodków wi¹¿¹cych-karbofunkcyjnych silanów (KFS) stanowi¹cych zwi¹zki o wzorze ogólnym XmRnSi(R'Y)4-m-n, gdzie R-grupa alkilowa (czêsto metylowa), R'-³añcuch alkilenowy, Y-grupa funkcyjna (np. Cl, NH2, NR2, OH, OCOR, NCO, CH2=CH, SH), X-grupa funkcyjna zdolna do hydrolizy (np. Cl, OH, OCOR), m = 1-3, n = 1-2, m + n = 3. Szczegó³owo omówiono równie¿ ró¿ne podstawowe dziedziny zastosowania KFS, takie jak modyfikacja w³aoeciwooeci nape³niaczy i polimerów, procesy zol-¿el oraz ochrona przed korozj¹. S³owa kluczowe: silanowe oerodki wi¹¿¹ce, karbofunkcyjne silany, silikony, modyfikacja polimerów, nape³niacze, nanonape³niacze, nanocz¹stki. CARBOFUNCTIONAL SILANES AND POLYSILOXANES. PART I. APPLICATIONS OF CARBO-FUNCTIONAL SILANES Summary-On the basis of literature data the general characteristics of binding agents, carbofunctional silanes (KFS) of general formula X m R n Si(R'Y) 4-m-n [where R-alkyl group (often methyl one), R'-alkylene chain, Y-functional group e.g. Cl, NH 2 , NR 2 , OH, OCOR, NCO, CH 2 =CH, SH, and X-functional group capable to hydrolysis e.g. Cl, OR, OCOR; m = 1-3, n = 1-2, m + n = 3] was presented. Various main areas of KFS applications such as modification of the properties of fillers or polymers, sol-gel processes and anticorrosion protection were discussed in detail.