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In this work, modified polycarboxylates were prepared by copolymerizing γ‐Methacryloxy propyl trimethoxyl silane (KH‐570) with acrylic acid and allyl polyoxyethylene ether. Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) indicate that silane copolymerized polycarboxylates have been successfully synthesized. The talc powder (TP) modified with synthesized polycarboxylate and modified polycarboxylates was blended with polyvinyl chloride (PVC) to prepare composite films. FTIR and x‐ray photoelectron spectroscopy (XPS) were used to determine changes in the surface properties of unmodified and modified TP. The effects of TP and polycarboxylate‐modified TP on the tensile properties, light transmission and moisture transmission of the PVC composite films were investigated. Compared with untreated TP filled PVC film, the PVC composite films filled with organosilicon polycarboxylate‐modified TP exhibit enhanced tensile strength, light transmittance, barrier, and other properties. Especially, the tensile strength of PVC composite film filled with 7 wt% Si0.5‐PCE modified TP is increased by 19.5% and the elongation at break is increased by 21.6%. In addition, the moisture permeability of the composite film is reduced by a maximum of 80.6% compared with the pure PVC film. [ABSTRACT FROM AUTHOR]

To replace traditional phthalate plasticizers, our previous research revealed that trioctyl citrate (CA) with an alkyl chain containing 8 carbon atoms (C8) exhibited excellent plasticizing properties. In order to delve deeper into the plasticization effects of CA isomers, CA with different side‐chain structures (C8‐Line, C8‐Branch, and C8‐Star) were synthesized by esterification reactions, and various CA/polyvinyl chloride (PVC) composite films with different CA contents were prepared using a solution casting method. The plasticization mechanisms of these isomers were systematically explored through experimental and molecular dynamics simulations. The results indicate that C8‐Branch demonstrates the optimal plasticizing effect, followed by C8‐Line, while C8‐Star exhibits poorer performance. The C8‐Branch/PVC composite system displays the best plasticizing effect, attributed to the strong interaction forces between the Cl atoms of PVC and the COO groups of CA. On the contrary, the formation of stable dipole pairs between C8‐Star and PVC is impeded by steric hindrance effects. The interaction between the two is predominantly dependent on the intertwining of the alkyl chains in C8‐Star with the PVC chains, also elucidating the observed higher migration rate in the C8‐Star/PVC system. This study provides technical guidance and theoretical basis for the optimized design of high‐performance CA/PVC composites. [ABSTRACT FROM AUTHOR]