Polyurethane-silica nanocomposites provided from perhydropolysilazane: Polymerization mechanism

Polyurethane-silica nanocomposites provided from perhydropolysilazane: Polymerization mechanism Polyhydroxyurethane-silica nanocomposites were synthesized with 2-ethyl-2-(((3-((2-(2-oxo-1,3-dioxolan-4-ly)ethyl)thio)propanoyl)oxy)methyl)propane-1,3-diylbis(3-((2-(2-oxo-1,3-dioxolan-4-yl)ethyl)thio)propanate), Tris-CC, and 1,3-diaminopropane in the presence of 5–30 wt% of perhydropolysilazane, PHPS, which is a precursor of silica, in one step. During the synthesis of nanocomposite, three reactions, which are formation of hydroxy group by ring opening polymerization of cyclic carbonate, conversion of PHPS into silica, and the formation of Si-O-C bond by reaction between hydroxy group formed by ring opening and SiH group of PHPS, were competitively proceeded. The competitive reaction mechanism for polyhydroxyurethane-silica nanocomposite was quantitatively analyzed by using propylene carbonate, PC, and propylamine as model compounds of Tris-CC and 1,3-diaminopropane by 1H NMR. The hydroxy group of polyhydroxyurethane was preferentially formed compared to the conversion of PHPS into silica, then the Si-O-C bond was formed between polyhydroxyurethane and PHPS until 5 h. The formation rate of Si-O-C bond was governed by the formation rate of the hydroxy group of polyhydroxyurethane. On the other hand, the conversion of PHPS to silica was preferentially performed than the formation of hydroxy group of polyhydroxyurethane over 5 h. The hydroxy group of polyhydroxyurethane was more slowly formed than the conversion of PHPS to silica over 5 h. Less competitive reaction between polyhydroxyurethane and PHPS occurred, which lead to the less formation of Si-O-C bond. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Polymer Elsevier

Polyurethane-silica nanocomposites provided from perhydropolysilazane: Polymerization mechanism

Loading next page...
 
/lp/elsevier/polyurethane-silica-nanocomposites-provided-from-perhydropolysilazane-0g44YmShTH
Publisher
Elsevier
Copyright
Copyright © 2017 Elsevier Ltd
ISSN
0032-3861
D.O.I.
10.1016/j.polymer.2017.12.023
Publisher site
See Article on Publisher Site

Abstract

Polyhydroxyurethane-silica nanocomposites were synthesized with 2-ethyl-2-(((3-((2-(2-oxo-1,3-dioxolan-4-ly)ethyl)thio)propanoyl)oxy)methyl)propane-1,3-diylbis(3-((2-(2-oxo-1,3-dioxolan-4-yl)ethyl)thio)propanate), Tris-CC, and 1,3-diaminopropane in the presence of 5–30 wt% of perhydropolysilazane, PHPS, which is a precursor of silica, in one step. During the synthesis of nanocomposite, three reactions, which are formation of hydroxy group by ring opening polymerization of cyclic carbonate, conversion of PHPS into silica, and the formation of Si-O-C bond by reaction between hydroxy group formed by ring opening and SiH group of PHPS, were competitively proceeded. The competitive reaction mechanism for polyhydroxyurethane-silica nanocomposite was quantitatively analyzed by using propylene carbonate, PC, and propylamine as model compounds of Tris-CC and 1,3-diaminopropane by 1H NMR. The hydroxy group of polyhydroxyurethane was preferentially formed compared to the conversion of PHPS into silica, then the Si-O-C bond was formed between polyhydroxyurethane and PHPS until 5 h. The formation rate of Si-O-C bond was governed by the formation rate of the hydroxy group of polyhydroxyurethane. On the other hand, the conversion of PHPS to silica was preferentially performed than the formation of hydroxy group of polyhydroxyurethane over 5 h. The hydroxy group of polyhydroxyurethane was more slowly formed than the conversion of PHPS to silica over 5 h. Less competitive reaction between polyhydroxyurethane and PHPS occurred, which lead to the less formation of Si-O-C bond.

Journal

PolymerElsevier

Published: Jan 17, 2018

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off