Synthesis of a novel betaine-type asphalt emulsiﬁer
and its investigation by online FTIR spectrophotometry
Received: 5 March 2012 / Accepted: 26 April 2012 / Published online: 17 May 2012
Ó Springer Science+Business Media B.V. 2012
Abstract A novel betaine-type asphalt emulsiﬁer, 3-(dodecyloxy)-2-hydroxypro-
pan-N-carboxymethyl-N,N-dimethylammonium chloride, has been synthesized in a
three-step reaction from lauryl alcohol, epichlorohydrin, dimethylamine, and
chloroacetic acid. The optimum reaction conditions were obtained for synthesis of
2-(dodecyloxymethyl)oxirane in the ﬁrst step. The yield reaches 75.7 % under the
optimum conditions of reaction temperature 50 °C, reaction time 5 h, feedstock
mole ratio of epichlorohydrin to lauryl alcohol 1.4, basicity 33.3 %. The structures
of the three products were identiﬁed by FTIR. Synthesis of 2-(dodecyloxymeth-
yl)oxirane in the ﬁrst step was monitored by online FTIR, and an intermediate was
detected. On the basis of the experimental data, a plausible reaction mechanism was
proposed for the reaction. The critical micelle concentration (CMC) of the ﬁnal
product is low, 8.8 9 10
mol/L. The surface tension at the CMC is 21.2 mN/m.
This product is an excellent emulsiﬁer for asphalt. The prepared bituminous
emulsion had high storage stability. The emulsiﬁer is a rapid-set asphalt emulsiﬁer.
Keywords Asphalt Á Emulsiﬁer Á Betaine Á Synthesis Á Online FTIR
Surfactants to emulsify water and asphalt are called asphalt emulsiﬁers. The prepared
solution is called a bituminous emulsion. Compared with hot asphalt, use of a
bituminous emulsion has the advantage of stronger adhesive power with mineral
aggregate, lower energy consumption, and less pollution of the environment.
Bituminous emulsions are widely used as pavement and building materials [1–3].
C. Huai Á L. Shi (&) Á N. Li
School of Chemistry and Chemical Engineering, South Campus, Shandong University,
Jinan 250061, People’s Republic of China
Res Chem Intermed (2013) 39:597–614