A UV-cured composite film was prepared by free free-radical photopolymerization from a blend containing oligomer cycloaliphatic polyurethane acrylate (CPUA) and reactive diluent trimethylolpropane trimethaacrylate (TMPTMA) with the same weight (coded as UT) in the presence of free free-radical photoinitiator Irgacure 754. It was proved to be a homogeneous system featuring only one phase by means of scanning electron microscopy (SEM). Cycloaliphatic epoxy resin (CER) was introduced to enhance mechanical properties of the UV-cured UT composite film in the presence of cationic photoinitiator Irgacure 250, and a series of UV-cured CPUA/TMPTMA/CER composite films with different component ratios were prepared by free radical/cationic hybrid UV UV-curing technique. Results of conversion curves, SEM, and Fourier- transform infrared spectroscopy illustrated that UT was cured faster than CER, leading to dynamically asymmetric photopolymerization-induced phase -separation behaviors. The thermal and mechanical properties were evaluated via thermal degradation analysis, dynamic mechanical analysis, and stress–strain curves. Surface properties such as pencil hardness, pendulum hardness, shrinkage rate, contact angle, flexibility, and glossiness were also studied. All these measurements revealed that component ratios, intermolecular attractions, photopolymerization velocities, and viscosities had remarkably influenced on the morphologies and applied properties of UV-cured composite films, and interpenetrating polymer network films had better comprehensive performances than other UV-cured composite films with different microstructures. POLYM. COMPOS., 36:1177–1185, 2015. © 2014 Society of Plastics Engineers

A series of hydroxy-terminated polyether-polydimethylsiloxane-polyether (α,ω-dihydroxy-(PE-PDMS-PE)) ABA triblock oligomers were synthesized from silanic fluids and methyl polyallyloxide polyethers. The reaction was a one-step solventless hydrosilylation reaction with chloroplatinic acid (CPA) catalyst in the presence of heat. These ABA oligomers were characterized via ¹H-NMR, ¹³C-NMR, ²⁹Si-NMR, FT-IR, and GPC to demonstrate that they exhibit a 100% linear ABA structure with a siloxane SiO chain in the center and polyether ethylene oxide (EO)/propylene oxide (PO) chains on the two sides terminated by hydroxy groups. The triblock oligomers were used to form thermoplastic polyurethanes (TPUs) using two-step solventless bulk polymerization. The investigation of triblock oligomers impact on TPUs mechanical properties, thermal performance, surface water repellency, and morphology performance were analyzed by Instron material tester, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), water contact angles (WCA), scanning electron microscope (SEM), and transmission electron microscope (TEM). DSC and TGA indicated that PE-PDMS-PE modified TPUs had a clear lower T_g under −120°C and the temperature of 50% weight loss was improved from 280 to 340°C. PE-PDMS-PE–modified TPU did not have the marked reduction on mechanical properties than pure polyether produced TPU. Tensile strength was maintained at 13 MPa and elongation was maintained at 300%. SEM and TEM were used to investigate the copolymers’ morphology performance and found that all PO PE-PDMS-PE had a pseudo-three phase separation. WCA analysis confirmed that PE-PDMS-PE–modified TPU had significantly improved hydrophobic performance because the silicone structure linked into TPU copolymers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42521.

A series of UV-curable, silicon-containing mixtures were prepared by adding different micro amounts of small molecular weight silicon-containing acrylate KH570 to an interpenetrating polymer network system composed of cycloaliphatic polyurethane acrylate, trimethylolpropane triacrylate, cycloaliphatic epoxy resin, free-radical photoinitiator Irgacure 754 and cationic photoinitiator Irgacure 250 with a weight ratio of 15 : 15 : 65 : 1 : 4. Hybrid coatings with different addition amounts of KH570 (0.2, 0.6, 1.0 wt %) were cured from the mixtures by UV-initiated free-radical/cationic dual curing technique. Final reactant conversions and photopolymerization rates of the hybrid UV-cured coatings were improved with the increase of KH570 content, as evaluated by conversion profiles. The morphologies and microstructures were characterized by scanning electron micro-scopic, atomic force micrographic, and fourier transform infrared spectrophotometer measurements. Thermal, mechanical, and surface properties of the hybrid UV-cured coatings were investigated. The increase in KH570 content caused a decrease in mechanical properties besides the breaking elongation. Thermo-gravimetric analysis revealed that the incorporation of silicon into cross-linked network structure resulted in high thermal stability. The surface properties of hybrid UV-cured coatings, such as hardness, contact angle, flexibility, and glossiness were also examined. It is found that transparent hybrid coating with the addition of 1.0 wt % KH570 exhibited a relatively higher contact angle as a direct result of a relatively higher hydrophobic surface. These researches showed that micro amounts of small molecular weight silicon-containing acrylate could greatly influence the morphologies of liquid nitrogen quenching cross sections and properties of hybrid UV-cured coatings and could be used to modify UV-cured coatings for some superior properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40655.

A new inverse emulsion polymerization and intercalation procedure in supercritical carbon dioxide (SCCO₂) was initially employed to synthesize polyaniline-montmorillonite (PANI-MMT) nanocomposites. The effect of chemical groups in MMT galleries on intercalation in SCCO₂ was investigated. The MMTs modified by different organic cationic surfactants were incorporated into the composite particles, and in unintercalated, partially delaminated or fully exfoliated state. The aminated MMT or fluorinated MMT were utilized to prepare conducting PANI-MMT nanocomposites with highly concentrated (12–25 wt% loading to monomer), fully exfoliated MMT platelets in SCCO₂. The structure and morphology of PANI-MMT nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction pattern (XRD), and transmission electron microscope (TEM). Thermogravimetry analysis (TGA) was performed to demonstrate the enhancement of thermal stability of the composites. SCCO₂ was shown to be more effective for impregnation, disaggregation and exfoliation of MMTs than isooctane, which indicates that SCCO₂ is an alternative solvent for synthesis of some intercalated composite materials, not only based on the environmental friendly characteristic of SCCO₂, but also owing to that SCCO₂ can play an important role in intercalative polymerization. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers