Synthesis and property of end‐functionalized poly(cis‐1,4‐butadiene) and its application to rubber compound

Abstract

This article describes the successful quasi-living polymerization of 1,3-butadiene (BD) to high cis content butadiene rubber (HCBR) and the terminal functionalization of HCBR for application to rubber compound. A catalyst system based on neodymium carboxylate and organoaluminum compounds was prepared and employed to polymerize BD. Polymerization resulted in mostly proportional growth of molecular weight to the conversion while maintaining molecular weight distribution in relatively narrow range. The reactivity of chain end after the completion of polymerization was confirmed by comparing UV absorbance of polymers before and after the addition of chromophore compound to the unterminated polymerization mixture, as measured with size exclusion chromatography (SEC). A variety of functionalizing agents, which can provide end-groups of polymer with potential affinity to silica surface, was explored. Among them, compounds with epoxy, ketone, and ketimine groups produced polymers with clear evidences of functionalization. The HCBR functionalized with epoxy-containing alkoxysilane compound was tested in silica-filled rubber compound and showed remarkable improvement of silica dispersity as seen by change of viscoelastic responses.

A Coarse-Grained Force Field for Silica–Polybutadiene Interfaces and Nanocomposites

“…Thus, the present study represents the first step within a broader, longer-term research project. For the polymer, we restrict our investigation to poly(cis-1,4-butadiene) [ 47 , 48 ]. The choice of this particular combination of materials is determined by its widespread use in the tyre industry, combined with its relative simplicity in terms of structure and chemical composition.…”

Fracture in Silica/Butadiene Rubber: A Molecular Dynamics View of Design–Property Relationships

“…This paper is devoted to the simulation of the mechanical properties of polybutadiene networks incorporating silica nanoparticles. This combination of materials has practical interest, 43 but it has also been adopted in more fundamental studies of reinforcement. 44 We have combined elements from our previous papers on silica 45 and butadiene networks 46 into a coherent model, adding the possibility of bond scission in order to model large deformations and fracture.…”

Amphiphilic Silicon Hydroxyl-Functionalized cis-Polybutadiene: Synthesis, Characterization, and Properties

“…The living polymerization of butadiene with Nd-based catalysts without chain transfer and termination reactions could be achieved only at extremely low temperature (−70 °C), and cis-PB with relatively high number-average molecular weight (M n ) of >410 kg•mol −1 was obtained. 29 The end-group-functionalized cis-PBs could be achieved by terminating the living cis-PB chains after coordination polymerization by adding appropriate functional agents such as epoxy, 30,31 ketone, 30 ketimine, 30 isocyanate compounds, 30 carboxyl compounds, 30 halogen, 32 aldehyde, 33 amide, 33 ester, 33 imidazolidinone, 33 pentamethyl siloxane, 34 and 3-glycidoxypropyltrimethoxysilane. 31,35 Unfortunately, the resulting end-group-functionalized cis-PBs with relatively low functionality were obtained due to the complex chemical mechanism and self-termination reaction.…”

“…The living polymerization of butadiene with Nd-based catalysts without chain transfer and termination reactions could be achieved only at extremely low temperature (−70 °C), and cis -PB with relatively high number-average molecular weight ( M n ) of >410 kg·mol –1 was obtained . The end-group-functionalized cis -PBs could be achieved by terminating the living cis -PB chains after coordination polymerization by adding appropriate functional agents such as epoxy, , ketone, ketimine, isocyanate compounds, carboxyl compounds, halogen, aldehyde, amide, ester, imidazolidinone, pentamethyl siloxane, and 3-glycidoxypropyltrimethoxysilane. , Unfortunately, the resulting end-group-functionalized cis -PBs with relatively low functionality were obtained due to the complex chemical mechanism and self-termination reaction. − On the other hand, the reversible chain transfer polymerization of butadiene with an Nd-based catalyst system was firstly reported by Nuyken and co-workers , and has been used to synthesize block copolymers and end-group-functionalized polymers . Polymer chains carrying hydroxyl groups introduce hydrogen bonds, which has been recognized as an effective way to build self-healing materials.…”