Synthesis and solution properties of a temperature-responsive PNIPAM–b-PDMS–b-PNIPAM triblock copolymer
- 483 Downloads
In this paper, we report the synthesis and self-assembly of a novel thermoresponsive PNIPAM60–b-PDMS70–b-PNIPAM60 triblock copolymer in aqueous solution. The copolymer used a commercially available precursor modified with an atom transfer radical polymerization (ATRP) initiator to produce an ABA triblock copolymer via ATRP. Small-angle neutron scattering (SANS) was used to shed light on the structures of nanoparticles formed in aqueous solutions of this copolymer at two temperatures, 25 and 40 °C. The poly(dimethylsiloxane) block is very hydrophobic and poly(N-isopropylacrylamide) (PNIPAM) is thermoresponsive. SANS data at 25 °C indicates that the solutions of PNIPAM–b-PDMS–b-PNIPAM copolymers form well-defined aggregates with presumably core–shell structures below cloud point temperature. The scattering curves originating from nanoparticles formed at 40 °C in 100% D2O or 100% H2O were successfully fitted with the Beaucage model describing aggregates with hierarchical structure.
KeywordsThermoresponsive PNIPAM SANS Polymerization Atom transfer radical polymerization (ATRP) Self-assembly
S.F. acknowledges the Czech Science Foundation Grant No. 15-10527J. Institute Laue–Langevin is acknowledged for beam time allocation. This work was also supported by the Ministry of Education, Youth and Sports of CR within the National Sustainability Program I (Project POLYMAT LO1507). We acknowledge Isabelle Grillo, ILL, France, for help with the data treatment. The work was supported within the program of Large Infrastructures for Research, Experimental Development and Innovation (Project No. LM2015050) and research project LG14037 financed by the Ministry of Education, Youth and Sports, Czech Republic.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 5.Kyriakos K, Aravopoulou D, Augsbach L, Sapper J, Ottinger S, Psylla C, Aghebat Rafat A, Benitez-Montoya CA, Miasnikova A, Di Z, Laschewsky A, Müller-Buschbaum P, Kyritsis A, Papadakis CM (2014) Novel thermoresponsive block copolymers having different architectures—structural, rheological, thermal, and dielectric investigations. Colloid Polym Sci 292:1757–1774CrossRefGoogle Scholar
- 6.Kyriakos K, Philipp M, Lin CH, Dyakonova M, Vishnevetskaya N, Grillo I, Zaccone A, Miasnikova A, Laschewsky A, Müller-Buschbaum P, Papadakis CM (2016) Quantifying the interactions in the aggregation of thermoresponsive polymers: the effect of cononsolvency. Macromol Rapid Commun 27:420–425CrossRefGoogle Scholar
- 10.Chiba A, Hashimoto T, Hasegawa H, Hadjichristidis N (2005) Study on micro-phase separation of polyethylene oxide-poly(2-vinylpylidine) block copolymer by small-angle x-ray scattering. Polym Prepr 54:767Google Scholar
- 17.Adelsberger J, Bivigou-Koumba AM, Miasnikova A, Busch P, Laschewsky A, Müller-Buschbaum P, Papadakis CM (2015) Polystyrene-block-poly (methoxy diethylene glycol acrylate)-block-polystyrene triblock copolymers in aqueous solution—a SANS study of the temperature-induced switching behavior. Colloid Polym Sci 293:1515–1523CrossRefGoogle Scholar
- 21.Lobry L, Micali N, Mallamace FC, Liao C, Chen SH (1999) Interaction and percolation in the L64 triblock copolymer micellar system. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 60:7076–7087Google Scholar
- 26.Mortensen K, Brown WYN (1993) Poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymers in aqueous solution. The Influence of Relative Block Size Macromolecules 26:4128–4135Google Scholar
- 31.Filippov SK, Bogomolova A, Kaberov L, Velychkivska N, Starovoitova L, Cernochova Z, Rogers S, Lau WM, Khutoryanskiy VV, Cook MT (2016) Internal structure of nanoparticles formed by self-assembly of temperature-responsive PNIPAM-b-PEG-b-PNIPAM triblock copolymers: NMR and SANS studies. Langmuir 32:5314–5323CrossRefGoogle Scholar
- 35.Hammouda B, Jia D, Cheng D (2015) Single-chain conformation for interacting poly(N-isopropylacrylamide) in aqueous solution. J Sci Technol 3:8Google Scholar
- 42.Bogomolova A, Filippov SK, Starovoytova L, Angelov B, Konarev P, Svergun DI, Sedlacek O, Hruby M, Stepanek P (2014) Study of thermosensitive amphiphilic poly-oxazolines of complex nature and their interaction with ionic surfactants. Hydrophobic, thermosensitive and hydrophilic moieties: are they equally important? J Phys Chem B 118:4940–4950CrossRefGoogle Scholar
- 44.Filippov SK, Lezov AV, Sergeeva O, Olifirenko A, Lesnichin S, Domnina NS, Komarova E, Almgren M, Karlsson G, Štepanek P (2008) Aggregation of dextran hydrophobically modified by sterically-hindered phenols in aqueous solutions: aggregates vs. single molecules. Eur Polym J 44:3361–3369CrossRefGoogle Scholar
- 48.Izawa K, Ogasawara T, Masuda H, Okabayashi H, Monkenbusch M, O’Connor CJ (2002) Growth process for fractal polymer aggregates formed by perfluorooctyltriethoxysilane. Time-resolved small-angle x-ray scattering spectra and the application of the unified equation. Colloid Polym Sci 280:725–735CrossRefGoogle Scholar