AbstractThis article deals with a novel, semi‐interpenetrating polymer network (semi‐IPN), composed of crosslinked chitosan (cr‐CS) with glutaraldehyde (GA) and polyether. The pH responsibility of swelling data shows that swelling reaches a maximum at pH = 3.19 and a minimum at pH = 13. The concentration of chitosan acetic acid solution, the amount of crosslinking agent, and polyether, have effects on the swelling behavior of the network. Stimulating‐response of the semi‐IPN, induced by abrupt changes of pH between 1 and 13, is discussed as well. © 1993 John Wiley & Sons, Inc.