Abstract

Poly(N-isopropylacrylamide) (PNIPAM) linear chains and spherical microgels were studied using laser light scattering. The volume change associated with the temperature dependence of the hydrodynamic radii of both the linear chains and the spherical microgels is continuous, in contrast to a discontinuous volume phase transition observed for a bulk PNIPAM gel with an identical composition. A reexamination of the volume phase transition theory shows that the phase transition temperature depends on the length of the subchain between two neighboring cross-linking points inside the gel. A comparison of the results of the linear chains and the spherical microgels suggests that the volume change of a polymer gel should be practically continuous because the inhomogeneity of the subchain length smears the volume phase transition. A possible explanation is also presented to rationalize the discontinuous volume phase transition observed in certain bulk PNIPAM gels, which is based on the bulk shear module of the gel a...

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.