The low surface energy of silicone rubber (SiR) makes it difficult to blend SiR with conventional rubbers such as solution styrene−butadiene rubber (SSBR) and natural rubber. In this study, to enhance the interface interaction between SiR and SSBR, trimethylolpropane tris(3-mercaptopropionate) (TMPMP) was carefully chosen to couple SiR and SSBR by in situ thiol-ene click reactions between mercapto groups of TMPMP and vinyl groups of SiR and SSBR. The reaction of TMPMP with SiR and SSBR was characterized via torque−time curves, element analysis, and the dissolving−swelling test. Accordingly, a two-step strategy was proposed to prepare SiR/SSBR composites. Transmission electron microscopy indicated that the two-step strategy reduced the phase domain size of the blend. The composite exhibited higher mechanical properties and lower hysteresis. The results would extend SiR applications.

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Halogen-free flame retardant – MP was successfully adopted to improve the comprehensive properties of the novel Si-TPE.

Tailoring silica–rubber interactions using TMPMP (TV0) and single (TV1), double (TV2) and triple (TV3) VTES modified TMPMP.

Two silane coupling agents, bis-(γ-triethoxysilylpropyl)-tetrasulfide (Si69) and vinyltriethoxysilane (A151), were selected to investigate their effects on structure and properties of silica-filled methyl vinyl silicone rubber (VMQ)/emulsion styrene butadiene rubber (ESBR) composites. The filler–rubber interactions were investigated via bound rubber content and solid-state 1H low-field nuclear magnetic resonance (NMR) spectroscopy, and the mass ratio of VMQ and ESBR in the rubber–filler gel was investigated by thermogravimetric analysis (TGA). The results revealed that VMQ showed a better compatibility with silica than ESBR. Compared with the A151 composite, the composite with Si69 showed the higher content of ESBR in rubber–filler gel, which resulted in the higher bound rubber content and the weaker Payne effect, and it also exhibited higher tensile strength, higher tear strength, better wear resistance, and lower hardness. However, the presence of Si69 reduced the crosslink efficiency of ESBR and completely inhibited the crosslinking of VMQ, which caused the composite to show higher tan δ value at 60 °C than the A151 composite.

The morphology of thin layers of Cu electrodeposited on 300 mm Ru substrates (deposited by plasma enhanced atomic layer deposition or PEALD) is studied. To reduce the terminal effect, a layer of physical vapor deposited (PVD) Cu is employed beneath the Ru, allowing the characterization of the electrodeposited Cu on PEALD Ru across an entire 300 mm substrate. The morphology of the initially deposited Cu is studied for different current densities and entry biases using topdown scanning electron microscopy (SEM) and post-plating sheet resistance measurements. Electrodeposited Cu particle densities increase with deposition current density, while the particle size appears to change little. Despite the presence of the Cu underlayer, the morphology of the Cu deposited on Ru varies across the wafer, with higher deposited particle densities observed near the wafer edge as compared to the rest of the wafer.

To overcome insoluble and low transmittance of the traditional polyimides (PIs), two kinds of novel fluorosilicone PIs were prepared. First, 1,4-bis (4-amino-2-trifluoromethylphenoxy) benzene, compound 3a, and 4,4 0 -bis(4-amino-2-trifluoromethylphenoxy)diphenyl ether, compound (3b), with 2-chloro-5-nitrobenzotrifluoride and p-hydroquinone or 4,4 0 -dihydroxydiphenyl ether were prepared. Second, hydrosilylation of nadic anhydride (NA) with 1,1,3,3-tetramethyldisiloxane (TMDS) yielded 5,5 0 -(1,1,3,3-tetramethyl-1,3-disiloxanediyl) bisnorbornane-2,3-dicarboxylic anhydride, compound (4). Initially, the conditions of the synthesis reaction such as reaction temperature, catalyst dosage, molar ratio of TMDS/NA, and reaction time on yield of compound 4 by the single factor approach were studied. The optimal reaction conditions were reaction temperature: 90 C, catalyst dosage: 1 ml (Pt% ¼ 0.37%), molar ratio of TMDS/NA: 1/1.8, and reaction time: 3 h. The yield was 74.6%. Finally, two kinds of new organosoluble, light-colored, and good thermal stable fluorosilicone PI compounds (5a-5b) were synthesized from compounds 3a-3b and 4 and 4,4 0 -hexafluoroisopropylidenediphthalic anhydride), prepared through a typical two-step polymerization method. The solubility of the novel fluorosilicone PI films of compounds 5a-5b and the traditional PI film (4,4 0 -diaminodiphenyl ether (ODA)-biphenyltetracarboxylic dianhydride, DIY) were contrasted. The result showed that the fluorosilicone PI films have good solubility. These PIs were soluble in amide polar solvents and even in less polar solvents. The glass transition temperatures of compounds 5a-5b were 229.1 and 186.7 C and the 5% and 10% weight-loss temperatures were 519.8 C and 539 C, respectively. These films had cutoff wavelengths of 331.8 and 318.6 nm. Due to these properties, these PIs could be used as aerospace, photoelectric, and microelectronic materials.

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