Preparation and properties of 1,2‐polybutadiene grafting with poly(1,3‐butadiene)‐block‐(dimethylsiloxane)

Abstract

The development of silica‐filling elastomers with high mechanical performance and good processability is still a great challenge. In this study, we fabricated siloxane‐grafted atactic 1,2‐polybutadiene (1,2‐PB) rubber through grafting poly(1,3‐butadiene)‐block‐(dimethylsiloxane) (PB‐b‐PDMS) onto 1,2‐PB molecular chains by coordination polymerization using a molybdenum (Mo)‐based catalyst system. The PB‐b‐PDMS with active double bonds was synthesized by anionic polymerization. Fourier transform infrared analysis (FTIR), elementary analysis, and GPC‐MALLS‐viscometer analyses verified the incorporation of PB‐b‐PDMS and the grafting structure in the resulting polymer. Scanning electron microscope (SEM), bound rubber testing, and dynamic mechanical analysis demonstrated that the graft‐modification with PB‐b‐PDMS improved silica dispersity in the 1,2‐PB matrix because the incorporation of siloxane groups provided stronger interfacial interaction with silica. Meanwhile, the graft‐modified 1,2‐PB exhibited lower Mooney viscosity, higher tensile strength, and lower heat build‐up than unmodified 1,2‐PB. This concept provides novel inspiration for the preparation of advanced rubber with promoted silica compatibility and mechanical performance.

Siloxanes—Versatile Materials for Surface Functionalisation and Graft Copolymers

“…A polybutadiene rubber, for application as a silica-filled elastomer, was produced by grafting a block copolymer of butadiene and dimethylsiloxane on polybutadiene [ 7 ]. The block copolymer was produced by sequential anionic polymerisation of butadiene and octamethyltetrasiloxane.…”

“…The Si-O bond is a highly versatile chemical linkage that can be found in a great variety of materials and molecules, linking together inorganic [ 1 , 2 , 3 ] and organic species [ 4 , 5 , 6 ], as well as being a building block for polymers [ 7 , 8 , 9 ] and sophisticated 3D oligomers [ 10 , 11 ]. In the role of linkage, the siloxane bond is robust, chemically resistant to an array of environments and easily established, e.g., via the reaction of silanes with organic or inorganic hydroxyl groups [ 6 , 12 , 13 ].…”

Toughness enhancement of polyamide 6,12 with intermolecular hydrogen bonding with 3‐pentadecylphenol

“…Polyamide 6,12 (PA6,12) is a well‐known engineering thermoplastic, which has been widely used in automotive, electrical, and medical application 1–3 . The PA6,12 has a typical structure of amide group and methylene chain in the main chain 4 .…”

“…Small molecules can also toughen polyamide due to plasticizing effect 16 . For instance, it has been reported that polyethylene glycol substantially improves PA6 toughness due to plasticizing effect 1 . Cai et al 16 synthesized a small molecule chain extender to modify PA6 performance, and its impact strength was ~1.7 times higher than that of the neat PA6 matrix.…”