Two series of sequential copolymers were synthesized by polymerization of 1,n-dibromoalkane (n = 4, 6, 8, 10, 12, 14 and 18) with 4, 4'- (hexafluoroisopropylidene) diphenol (6FBA) and bisphenol-A (BA). The flexible aliphatic segment length changes from 4 to 21Å corresponding to 4 to 18, -CH₂-, groups. X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and atomic force m icroscopy (AFM) were used to characterize the copolymers. The influence of the flexible aliphatic segment length on the surface composition of the BA and 6FBA sequential copolymers was investigated. AFM was utilized to study the organization of spherulites and the crystallization process of the BA copolymer with n=8. The formation of nuclei and the growth of lamellae were st...[ Read more ]

Two series of sequential copolymers were synthesized by polymerization of 1,n-dibromoalkane (n = 4, 6, 8, 10, 12, 14 and 18) with 4, 4'- (hexafluoroisopropylidene) diphenol (6FBA) and bisphenol-A (BA). The flexible aliphatic segment length changes from 4 to 21Å corresponding to 4 to 18, -CH₂-, groups. X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and atomic force m icroscopy (AFM) were used to characterize the copolymers. The influence of the flexible aliphatic segment length on the surface composition of the BA and 6FBA sequential copolymers was investigated. AFM was utilized to study the organization of spherulites and the crystallization process of the BA copolymer with n=8. The formation of nuclei and the growth of lamellae were studied. Nuclei appeared first as 10 nm dots. Some disintegrated and others grew and developed into spherulites. The lamellae that developed from the nuclei bred more lamellae, which in turn induced secondary nucleation and branching of lamellae and finally led to a spherical appearance. New depictions of the polymer crystallization mechanism are summarized based on the experimental observations.