Eur. Phys. J. E 5, 5-12

Triblock copolyampholytes from 5-(N,N-dimethyl amino)isoprene, styrene, and methacrylic acid: Synthesis and solution properties

R. Bieringer¹, V. Abetz¹ and A.H.E. Müller<sup>1, 2

1</sup>  Makromolekulare Chemie II, Universität Bayreuth, 95440 Bayreuth, Germany
²  Bayreuther Zentrum für Kolloide und Grenzflächen, 95440 Bayreuth, Germany

volker.abetz@uni-bayreuth.de

(Received 15 March 2000 )

Abstract
ABC triblock copolymers of the type poly[5-(N,N-dimethyl amino)isoprene]-block-polystyrene-block-poly(tert-butyl methacrylate) (AiST) were synthesized and hydrolyzed to yield poly[5-(N,N-dimethyl amino)isoprene]-block-polystyrene-block-poly(methacrylic acid) (AiSA) triblock copolyampholytes. Due to a complex solubility behavior the solution properties of these materials had to be investigated in THF/water solvent mixtures. Potentiometric titrations of AiSA triblock copolyampholytes showed two inflection points with the A block being deprotonated prior to the Ai hydrochloride block thus forming a polyzwitterion at the isoelectric point (iep). The aggregation behavior was studied by dynamic light scattering (DLS) and freeze-fracture/transmission electron microscopy (TEM). Large vesicular structures with almost pH-independent radii were observed.

PACS
61.16.Bg - Transmission, reflection and scanning electron microscopy (including EBIC).
61.25.Hq - Macromolecular and polymer solutions; polymer melts; swelling.
81.05.Lg - Polymers and plastics; rubber; synthetic and natural fibers; organometallic and organic materials.


© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2001