Towards Bioelastomers via Coordination Polymerization of Renewable Terpenes Using Neodymium-Based Catalyst Systems

Abstract

Syntheses of biolestomers through the coordination polymerization of terpenes, such as ocimene (Oc), β-myrcene (My) andtrans-β-farnesene (Fa), using catalyst systems based on neodymium versatate (NdV3) are reported in this work. All polymerization products were characterized by size exclusion chromatography, differential scanning calorimetry and nuclear magnetic resonance in order to determine their macromolecular, thermal and structural characteristics. The NdV3in combination with diisobutylaluminum hydride as cocatalyst and diethylaluminum chloride (DEAC) as halogen source was found effective for Oc polymerizations providing polyocimenes with molecular weights (Mn) in the order of 20 to 57 Kg/mol, broad molecular weight distributions (Mw/Mn) since 3.8 until 8.2, preferablycis-1,4 content (61-69 %) and glass transition temperatures (Tg) in the range of-30 to-26 °C. On the other hand, the same NdV3but now activated by modified methylaluminoxane and DEAC was found considerably active in My and Fa polymerizations, affording polymyrcenes and polyfarnesenes withMnbetween 155 and 243 Kg/mol, as well asMw/Mnranging between 3.1-3.9 and 1,4 content values were found higher than 94 % for this subfamily of polyterpenes, being the 3,4 content the complement for completing 100 %. Moreover, it was demonstrated thatTgof polyterpenes studied depends on the size of pendant group, shifting it towards lower temperatures as increasing the size of the pendant group.

Introducing random bio-terpene segments to high cis-polybutadiene: making elastomeric materials more sustainable

“…As well as have good control of the molecular weight characteristics of the polymers. [24][25][26] Thermal behavior of the homopolymers and copolymers…”

“…Moreover, high cis-1,4 content promotes the strain-induced crystallization of rubbers. [24][25][26] In this work, we report the copolymerization of 1,3-butadiene with the bio-based terpenes b-myrcene and trans-b-farnesene, via CCTP using a tertiary catalytic system based on Nd. With this approach, we can obtain more sustainable elastomers with a quasilinear relationship between the composition of the terpenic monomer and the glass transition temperature (T g ).…”

Fully Bio-Based Elastomer Nanocomposites Comprising Polyfarnesene Reinforced with Plasma-Modified Cellulose Nanocrystals

“…Currently, trans -β-farnesene is commercially produced by fermenting cane sugar using a genetically modified yeast [ 2 ]. This biological monomer has already been successfully polymerized by free radicals [ 3 ] and anionic [ 4 ] polymerization techniques; however, only the polymerization by coordination provides polyfarnesene (PF) with a high stereospecificity [ 5 , 6 ], which, depending on the application, generally results in a better performance. The applications of elastomers at an industrial level commonly demands reinforcements linked to the use of different types of fillers to improve the materials’ final properties, such as mechanical performance.…”

Bio-elastomers based on polyocimene synthesizedviacoordination polymerization using neodymium-based catalytic systems

“…Rare-earth metal-based catalysts have been reported for their efficiency to polymerize 1,3-dienes with high catalytic activities, yielding polymers with good control in both their stereoregularity and molecular weight characteristics. [10][11][12][13][14] The potential of such catalytic systems has lately been extended to the polymerization of unconventional bio-terpenes, such as b-myrcene, 15,16 b-farnesene, 17,18 and (E)-a-ocimene, 18,19 obtained from renewable resources. Although the aforesaid monomers produce bio-elastomers with low carbon footprint and acceptable performance, they fall short when compared to conventional petroleum-based materials in terms of cost-efficiency and performance.…”

“…22 Recently, our research group has investigated the polymerization of 1,3-butadiene and b-myrcene using Nd-based catalytic systems. 18,[23][24][25] However, to the best of our knowledge, no reports have been led for ocimene polymerization using Nd-based catalytic systems. Therefore, in this study we evaluate two different catalysts: neodymium isopropoxide (Nd(Oi-Pr) 3 ) and neodymium versatate (NdV 3 ) (see Fig.…”