Introduction
Amphiphilic polymers composed of hydrophilic and
hydrophobic segments a exhibit characteristic tendency
to undergo self-organization processes in the presence of
solvents, forming superstructures on a mesomorphic
scale [1, 2, 3, 4, 5, 6]. Such amphiphilic polymers prove
more advantageous than simple surfactants in view of
the diversity in the arrangements of the hydrophobic
and hydrophilic segments, the length and branching of
the hydrophobic tail, the molecular architecture afforded
by varying the polymer geometry and, thus, enabling the
formation of versatile mesophase structures. Different
types of polymers, block copolymers [7, 8, 9, 10], stars,
graft copolymers [11, 12, 13, 14, 15], segmented block
copolymers [16, 17] and polysoaps [18, 19, 20, 21, 22, 23]
contributing to the versatile molecular architecture with
distinct subgroups provide classic examples of polymeric
amphiphiles. The kinds of aggregated structures exhib-
ited by a polymeric amphiphile, and arising from various
kinds of forces, depend on the amphiphilic architecture
and the polarity of the solvent. Polymeric amphiphiles,
especially those consisting of ionizable comonomers,
exhibit interesting solution properties. The solution
ORIGINAL CONTRIBUTION
Colloid Polym Sci (2002) 280: 886–891
DOI 10.1007/s00396-002-0697-9
G. Baskar
S. Ramya
A.B. Mandal
Synthesis and solution properties of comblike
polymers from octadecyl methacrylate and
acrylic acid
Received: 23 October 2001
Accepted: 8 March 2002
Published online: 22 May 2002
Ó Springer-Verlag 2002
G. Baskar (&)
Industrial Chemistry Division,
Central Leather Research Institute,
Adyar, Chennai 600 020, India
E-mail: gitsri@hotmail.com
Tel.: +91-44-4911386/4911108
Fax: +91-44-4911589
S. Ramya Æ A.B. Mandal
Chemical Laboratory,
Inorganic and Physical Chemistry Division,
Central Leather Research Institute,
Adyar, Chennai 600 020, India
Abstract Amphiphilic polymers
consisting of a statistical distribution
of octadecyl methacrylate (ODMA)
and acrylic acid in respective molar
ratios of 83–22 and 17–78 mol%
and in a molecular-weight range of
2.35–4.70·10
4
gmol
–1
have been
synthesized. The series of polymers
consisting of various mole fractions
of ODMA and acrylic acid are ex-
pected to exhibit unique character-
istics resembling ionomer to
hydrophobically modified polyelec-
trolytes. The changes in the I
3
/I
1
emission intensity ratios of pyrene,
occurring in the presence of tetra-
hydrofuran (THF) solutions of the
polymers have been taken as the
main basis for inferring solution
structures. The polymers are found
to form random-coil to collapsed-
coil/aggregated structures in THF
solvent depending on the copolymer
compositions. The polymer consist-
ing of 83 mol% ODMA and
17 mol% acrylic acid behaves as an
ionomer, capable of forming col-
lapsed-coil structures at concentra-
tions of 0.02 gml
–1
and above as
shown by a very high I
3
/I
1
of 1.20
(I
3
/I
1
of pyrene in THF is 0.85). In
contrast, the poly(octadecyl meth-
acrylate) homopolymer and the sets
of copolymers consisting of a very
high proportion of acrylic acid to an
extent of 73 mol% and above con-
tribute to almost negligible or very
small changes in I
3
/I
1
similar to the
homopolymer, poly(octadecyl
methacrylate), suggesting the for-
mation of random-coil structures.
Keywords Comblike polymers Æ
Copolymer of octadecyl methacry-
late and acrylic acid Æ Solution
properties in tetrahydrofuran Æ
Fluorescence