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ABSTRACT: Processibilities of silicone composites were always a problem for their high content of SiO2 powders. This article found that the substitution of silicone resins for linear polydimethylsiloxanes (PDMS) made processibilities easier. Three silicone resins (MQ1.0, MQ1.1, and MQ1.2) with clarified chemical structures (by FT IR, 29Si NMR, and GPC) were adopted. Their shearing viscosities [η( γ ̇)] were greatly higher than PDMS with higher molecular weight, which could be assigned to stronger molecular interactions as surface tension and flowing activation energy ΔE indicated. On the contrary, η( γ ̇) of MQ‐PDMS binary blends greatly decreased to that even lower than either components (about 85% utmost decrease comparing to PDMS), for the variation of molecular interaction rather than dilution effect. Furtherly, when PDMS were partly replaced with MQ resins, process time of PDMS–SiO2 silicone composites were greatly shortened (from >6 to 2 h), while with better SiO2 dispersion (Mooney viscosity greatly decreased from 30.0 to 5.0 MU). Better dispersion of SiO2 fillers in composites could be confirmed by SEM and mechanical properties. For the better dispersion, mechanical properties of composites were improved with higher elastic modulus, higher tensile strength, and higher hardness, especially with higher elongation at break (utmost increased from 190% to 277%). © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46445. [ABSTRACT FROM AUTHOR]

The terpolymers (PASA) with acrylamide (AM), butyl styrene (BST), and sodium 2‐acrylamido‐2‐methylpropane sulfonate (NaAMPS) were synthesized by the micellar free radical copolymerization technique. The polymer composition was determined by the elemental analysis, and the block structure of PASA was characterized directly by DSC measurement. Incorporation of NaAMPS into the terpolymers may improve the water solubility and intermolecular association, and the feed amount of BST, sodium dodecyl sulfate (SDS) amount, and the total monomer concentration in the polymerization can influence apparently the viscosities of PASA. The polymer exhibits excellent viscosification effect, salt‐thickening, temperature‐thickening, thixotropy, pseudoplastic behavior or shear‐thickening relative to the BST content in PASA, excellent antiaging property at 85°C, and a dramatic increase in solution viscosity by the addition of little amount of SDS. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4027–4038, 2007 [ABSTRACT FROM AUTHOR]