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Amphiphobic organic–inorganic hybrid coating materials have been prepared by sol–gel technique in two steps. In the first step, fluorinated polymethylhydrosiloxane precursor was synthesized by hydr...

Polyurethane (PU) coatings were prepared using siloxane polyol [poly(dimethyl siloxane), PDMS], polyether polyol [poly(propylene oxide glycol), PPG], and polyester polyol [poly(tetramethylene adipa...

The Al(OH)3/acrylic copolymer latexes were synthesized through the emulsion polymerization of acrylic monomers, butyl acrylate and 2-ethylhexyl acrylate in the presence of surface-functionalized Al(OH)3 filler particles. The polymerization was stabilized by polyoxyethylene (50) nonyl phenyl ether (NP-1050, nonionic surfactant) and ammonium (POE) alkyl aryl ether sulfate (EU-S133D, anionic surfactant) to produce stable composite latexes. The improved compatibility of Al(OH)3 surface with acrylic monomers was achieved by the modification with 3-(trimethoxysilyl) propyl methacrylate (γ-MPS). Transmission electron microscopy showed that nano-sized Al(OH)3 particles were slightly agglomerated in the copolymer latex. When pristine Al(OH)3 was used as a filler or γ-MPS-modified Al(OH)3 particles were added above 30 wt% with respect to monomers, unstable latexes were obtained, which were partially precipitated out on standing for prolonged time. The flame retardation effect was not apparent with the incorporation...

On the basis of the stereocomplex formation between poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA), the stereocomplexation-induced surface properties of enantimeric polylactide blends were inverstigated by electron spectrometer for chemical analysis (ESCA) and contact angle measurements as a function of a degree of complexation. The complexation of blends was controlled by using the stereochemical polylactides (stPLAs) with percent D repeat unit contents (optical purity) of 100, 98, 95, 90, and 85%. The PLLA-b-poly(dimethyl siloxane) (PDMS)-b-PLLA triblock copolymer, instead of PLLA was used as a surface probe material because of the high surface segregation of PDMS blocks. From ESCA measurements, the surface segregation of PDMS of PLLA-b-PDMS-b-PLLA/stPLA blends with ≤10% optical impurity was rapidly decreased with a degree of complexation. However, the uncomplexed blends >10% optical impurity showed that the surface segregation of PDMS was nearly that of PLLA-b-PDMS-b-PLLA. Similar behaviors were obs...

This study investigated the stereocomplex-induced surface structure of enantiomeric poly(lactide) (PLA) blend films by differential scanning calorimeter, electron spectrometer for chemical analysis, and contact angle measurements. The design of the blend systems is based on principles of surface segregation of a modified component with a low surface energy, fluorocarbons (F), as an end group. The two blend systems, uncomplexed (F-l-PLA/l-PLA) and complexed (F-l-PLA/d-PLA), showed quite different surface structures: the surface segregation of fluorocarbon groups in the (F-l-PLA/l-PLA) blend film was observed while the surface structure of the (F-l-PLA/d-PLA) blend film was similar to its bulk one. This indicates that the interchain interaction to form stereocomplexes between l- and d-PLA is strong enough to overcome the driving force of fluorocarbon groups toward the surface.