Synthesis and Characterization of Organosilicon Sheet and Tube Polymers

• Published in: Chemistry of materials Vol. 13; no. 11; pp. 4269 - 4277
• Main Authors: Chao, Timothy C, Katsoulis, Dimitris E, Kenney, Malcolm E
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 19-11-2001
• Subjects: Applied sciences; Exact sciences and technology; Inorganic and organomineral polymers; Physicochemistry of polymers; Preparation; Chemical modification; Molecular structure; Morphology; Preparation; Silylation; Supramolecular structure; Hydrosilylation; Silicates; Experimental study; Siloxane polymer
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm0014029

The synthesis and characterization of some organosilicon sheet and tube polymers derived from silicates are described. The sheet silicates used are apophyllite (KCa4Si8O20(F,OH)·8H2O), kenyaite (Na2Si22O45·9H2O), magadiite (Na2Si14O29·7H2O), and silinaite (NaLiSi2O5·2H2O). The tube silicate used is K2CuSi4O10. The organosilicon sheet and tube polymers are made by silylation of sheet or tube silicates using a variety of nonfunctional and functional silylating agents. The formula of representative sheet and tube polymers made by silylation with trimethylchlorosilane is [((CH3)3SiO) x (HO)1 - x SiO1.5] n . The alkenyl-functional sheet and tube polymers are further elaborated by using hydrosilylation. The formula of representative sheet and tube polymers made by hydrosilylation of vinyldimethylsiloxy polymers with pentamethyldisiloxane is [((CH3)3SiO(CH3)2Si(CH2)2(CH3)2SiO) x (HO)1 - x SiO1.5] n . The polymers are characterized by FTIR, XRD, XPS, SEM, and solid state 29Si NMR. The characterization data demonstrate that ≈60% of the polymer surface silicon atoms carry pendent organosilicon groups, and the remaining silicon atoms carry silanol groups. These polymers are hydrophobic and they maintain the sheet or tube morphology both before and after the silylation and hydrosilylation reactions.