The present invention relates to polymer-brush modified fillers and methods, compositions and processes of modification of fillers and more particularly fillers useful in dental materials and other compositions that exhibit higher mechanical strength, longer hydrolytic stability, lower polymerization stress and improved wear and abrasion resistance. The present invention provides a method for making a polymer-brush modified filler comprising: providing a filler material; silanizing the filler material with a silane; and reacting the silanized filler with a telechelic oligomer. The present invention further provides a method of preparing a shaped dental prosthetic device for use in a human mouth comprising: dispensing a mixture having at least one monomer and a polymer brush modified filler; shaping the mixture; and photopolymerizing the mixture.
Mode of Activation of Cobalt(II) Amides for Catalytic Hydrosilylation of Alkenes with Tertiary Silanes
作者:Yang Liu、Liang Deng
DOI:10.1021/jacs.6b12938
日期:2017.2.8
capable of catalyzing alkene hydrosilylation in the absence of external activators are rarely known, and their activation mode has remained poorly understood. We present here that cobalt(II) amide complexes, [Co(N(SiMe3)2)2] and its NHC adducts [(NHC)Co(N(SiMe3)2)2] (NHC = N-heterocycliccarbene), are effective catalysts for the hydrosilylation of alkenes with tertiary silanes. Mechanistic studies
在没有外部活化剂的情况下能够催化烯烃氢化硅烷化的钴 (II) 配合物很少为人所知,并且其活化模式仍然知之甚少。我们在此提出钴 (II) 酰胺配合物 [Co(N(SiMe3)2)2] 及其 NHC 加合物 [(NHC)Co(N(SiMe3)2)2](NHC = N-杂环卡宾)是烯烃与叔硅烷氢化硅烷化的有效催化剂。机理研究表明,钴 (II) 酰胺可以与氢硅烷反应形成钴 (I) 物质、甲硅烷基酰胺和氢,作为进入真正催化活性物质的入口,大概是钴 (I) 物质,用于钴催化氢化硅烷化反应。
MODIFIED HYBRID SILICA AEROGELS
申请人:Rhine Wendell E.
公开号:US20120136079A1
公开(公告)日:2012-05-31
Disclosed and claimed herein are hybrid silica aerogels containing non-polymeric, functional organic materials covalently bonded at one or both ends to the silica network of the aerogels through a C—Si bond between a carbon atom of the organic material and a silicon atom of the aerogel network. Methods of their preparation are also disclosed.