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[(BA-C8) 18 –(6FBA)] n was synthesized by condensation polymerization of poly(bisphenol A- co -octane) containing 18 repeat units with bromine end groups, (Br–(BA-C8) 18 –Br), and 4,4′-(hexafluoroisopropylidene)diphenol (6FBA). This copolymer was confirmed to be semicrystalline after a single melting temperature was detected by differential scanning calorimetry. The changes in the surface chemical composition were measured using time-of-flight secondary ion mass spectrometry and X-ray photoelectron spectroscopy, the changes in the surface energy were measured using contact angle measurements, and the changes in the surface morphology were detected using atomic force microscopy as the copolymer crystallized. A decrease in the surface fluorine concentration with time was detected because of the movement of the low surface energy units (6FBA) to the bulk during the development of the crystalline phase. This result shows that the decrease in the enthalpy as a result of crystallization overcomes the increase in the surface free energy due to the migration of the low surface energy units to the bulk and the decrease in entropy due to demixing.

Poly(styrene) (PS), poly(2,3,4,5,6-pentafluorostyrene) (5FPS) and their random copolymers were prepared by bulk radical polymerization. The spin-cast polymer films of these polymers were analyzed using X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The surface and bulk compositions of these copolymers were found to be same, implying that surface segregation did not occur. The detailed analysis of ToF-SIMS spectra indicated that the ion fragmentation mechanism is similar for both PS and 5FPS. ToF-SIMS quantitative analysis using absolute peak intensity showed that the SIMS intensities of positive styrene fragments, particularly C 7 H 7 + , in the copolymers are higher than the intensities expected from a linear combination of PS and 5FPS, while the SIMS intensities of positive pentafluorostyrene fragments are smaller than expected. These results indicated the presence of matrix effects in ion formation process. However, the quantitative approach using relative peak intensity showed that ion intensity ratios are linearly proportional to the copolymer mole ratio when the characteristic ions of PS and 5FPS are selected. This suggests that quantitative analysis is still possible in this copolymer system.

Banded spherulites of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-3HV)) random copolymer were prepared by isothermal crystallization at 90 °C for 10 h. Using tapping-mode atomic force microscopy (AFM), the concentric periodic ridges and valleys on the surface of the banded spherulites of this polymer were found to consist of edge-on and flat-on lamellae, respectively. The periodic concentric ridges and valleys observed by AFM corresponded to the periodic extinction rings observed by polarized optical microscopy. AFM measurements showed that the interaction between the AFM probe and the sample surface can be significantly influenced by lamellar orientation.

The polymers BA-C8 and 6FBA-C8 were obtained by condensation polymerization of 1,8-dibromo-octane with bisphenol A and 4,4′-(hexafluoroisopropylidene)diphenol, respectively. A blend (BA-C8/6FBA-C8 (80/20)) containing 80 wt% of BA-C8 and 20 wt% 6FBA-C8 was prepared. Only one glass transition temperature was detected using a differential scanning calorimeter, suggesting that the blend is miscible. The surface chemical and morphological properties of the blend were studied as BA-C8 crystallized using atomic force microscopy, X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry and contact angle measurements. The results of the surface analyses showed that the surface of the blend was found to be enriched in the 6FBA-C8 polymer, especially at the crystalline regions. The crystalline regions were found to be raised above the amorphous regions. Surface segregation and crystallization were the two main factors that contributed to the changes in the chemical composition and morphology of the surface.

A blend of poly(epsilon-caprolactone) (PCL) and poly(vinyl chloride) (PVC) with 90 wt % PCL was prepared. Two films of this blend, which were grown at 35 and 45 degrees C, showed the absence and presence of banded spherulites, respectively. A detailed examination conducted with time-of-flight secondary ion mass spectrometry (ToF-SIMS) found that the surface composition of the film grown at 45 degrees C was related to its structure, which was shown to contain ridges and valleys. Phase images obtained using atomic force microscopy (AFM) indicated that the ridges and valleys consisted of edge-on and flat-on lamellae, respectively. ToF-SIMS imaging revealed that PVC and PCL were located mainly on the surface of the valleys and ridges, respectively. This morphology-driven surface segregation was caused by the difference in the surface energy between the flat-on and edge-on lamellae.