Synthesis And Properties Of Polytitanosilane Polymers By Direct Condensation

Polytitanosiloxane is an organic-inorganic hybrid materials, organic-inorganic hybrid refers to the organic polymer which contain hetero atom in organic polymer. It is a material which across boundaries of a "composite", so this hybrid material can have advantages of both organic and inorganic. Organic polymer is always easy curing, the operate construction is simple but don’t have high temperature strength ability; inorganic material can resist high temperature but it is usually brittle. If the two performances can be together, it can give common advantages of organic polymer and inorganic materials which can be a new type of hybrid material. Polytitanosilane is expected to achieve the above properties of organic-inorganic hybrid materials. In this study, polytitanosilane were synthesized by direct condensation, product properties were characterized, discussed the application of the polymer. This polytitanosilane can be used in high-temperature adhesive fields.1. Tetrabutyltitanate method is a rapid reaction process, the discussion of the reaction conditions determined the best reaction temperature is 30 ℃. The formed molecule is low degree of polymerization, the short segment of the final product molecules can be well dissolved in benzene, toluene and carbon tetrachloride.2. For polytitanosilane oligomer, polytitanosilane oligomer still retains the silicone material characteristics of high temperature resistance, the glass transition temperature is about-120℃.3. Titanium tetrachloride was used to synthesis polytitanosilane oligomer, but the product is less stable, selection titanate and hydroxysilane direct condensation reaction is appropriate.4. Different titanates as the titanium source were introduced into the silicone system, the study found; tetrabutyltitanate and tetraisopropyltitanate were more suitable as reaction raw materials. Using boronic acid hydroxylated siloxane, without adding demonized water method can synthesize polytitanosilane polymer contain different active end groups.5. Epoxy open-loop didn’t occurde by direct condensation, by derect method epoxy polytitanosilane retains epoxy group. For the synthesis of vinyl polytitanosilane, end-methoxy shows higher activity than the end-ethoxy, this shows the similar point with sol-gel method. The method is also applicable to the synthesis of polytitanosilane which contain methacryloxy and polytitanosilane which contain diethyl amino.6. For polytitanosilane-modified phenolic’s heat-resistant test, its char yield at high temperatures can basically meet the char yield commercially available of boron phenolic. Char yield at 950℃ increase from 64.87% to 70.41%. By XRD tests, high temperature performance is due to the occurrence of a phase transition of the produce, converted to anatase titanium dioxide. DTG analysis also showed that the introduction of the polytitanosilane polymer changeed the thermal degradation of phenolic resin.7. Polytitanosilane-modified phenol to 45 steel adhesion tests showed that the addition of polytitanosilane polymers can enhance the adhesion of 45 steel, the amount of polytitanosiloxane in phenolic resin should be controlled at 10%-20%.