SYNTHESIS AND CHARACTERIZATION OF MONODISPERSE ALPHA OMEGA-DIVINYLPOLYDIMETHYLSILOXANE AND OMEGA-VINYLPOLYDIMETHYLSILOXANE

Omega-vinylpolydimethylsiloxanes (omega-PDMS) and alpha,omega-divynilpolydimethylsiloxanes (alpha,omega-PDMS) have been synthesized by anionic polymerization of hexamethylcyclotrisiloxane (D3). The reactions were carried out in n-hexane and tetrahydrofuran (THF), respectively. The initiator was n-butyl-lithium (n-BuLi); tetrahydrofuran was used as an electron donor compound to promote the polymerization of D3. The synthesized polymers have been characterized by infrared (FTIR), proton nuclear magnetic resonance spectroscopy (NMR), light scattering (LALLS), and gel permeation chromatography (GPC). Molecular weights ranging from 20,000 to 100,000 were obtained with relatively narrow molecular weight distributions; Mw/Mn < 1.25.