We study the microphase segregation of molten randomly grafted copolymers (RGCs) using a Landau field theory. Under one wave number approximation, we find three equilibrium ordered microphases: lamellar phase (LAM), hexagonal cylinder phase (HEX), and bcc sphere phase (BCC). The stability of these phases strongly depends on the architectural parameters describing the RGC chains (e.g., the backbone length, the branch length, and the number of branches). Our calculation reveals that RGCs with high average composition of backbone monomers or with low branching density tend to form LAM microstructures. For a small average composition of backbone monomers, HEX and BCC microphases appear in turn with increasing branching density. Independent of the architectural parameters and composition, the disorder to order transition for molten RGCs is always from the disordered phase to the LAM microphase. The physical reasons underlying this behavior and experimentally testable predictions are discussed.
Skip Nav Destination
Article navigation
15 August 2001
Research Article|
August 15 2001
The phase diagram of molten randomly grafted copolymers
J. Chem. Phys. 115, 3401–3405 (2001)
Article history
Received:
December 04 2000
Accepted:
May 08 2001
Citation
Shuyan QiArup K. Chakraborty; The phase diagram of molten randomly grafted copolymers. J. Chem. Phys. 15 August 2001; 115 (7): 3401–3405. https://doi.org/10.1063/1.1382857
Download citation file:
