Facile Preparation of Supertoughened Polylactide-Based Thermoplastic Vulcanizates without Sacrificing the Stiffness Based on the Selective Distribution of Silica

Abstract

Blending with elastomers is one of the most effective strategies for toughening polylactide (PLA) but faces the challenge of a sharp decline in stiffness. In this work, PLA/epoxidized natural rubber (ENR)/silica (SiO2) thermoplastic vulcanizates (TPVs) with balanced stiffness–toughness were designed via dynamic vulcanization. The PLA/ENR/SiO2 TPVs exhibited a cocontinuous structure in which SiO2 nanoparticles were regulated to selectively distribute in the ENR phase. SiO2 nanoparticles enhanced the mechanical strength and thickness of ENR network, resulting in efficient toughening of PLA without sacrificing its stiffness. With 20 phr SiO2, the TPVs showed an excellent cryogenic impact toughness of 54.5 kJ/m2 at 0 °C, which was 8.3 times that of the PLA/ENR blend. Meanwhile, incorporation of SiO2 made the TPVs sustain a high retention rate of the tensile strength (98.2%). The synergistic toughening mechanism of SiO2 nanoparticles and ENR was investigated via a series of testing methods, proposing a feasible approach to fabricate high-performance TPVs.

Design Principles of Interfacial Dynamic Bonds in Self‐Healing Materials: What are the Parameters?

“…[175][176][177][178] The concept of covalently cross-linked networks in elastomers has been studied extensively in vulcanized rubber in the early 1930s. [179][180][181] In the subsequent section, we will highlight the critical underlying mechanisms and design features of self-healing materials via reversible covalent cross-linked networks. In doing so, several recent dynamic covalent chemistries will be discussed.…”

Silica‐reinforced ethylene propylene diene monomer/polypropylene thermoplastic vulcanizates with interfacial compatibilized by methylacrylate

“…It stands to the reason that the fully curing of rubber phase and the decreasing diameter will lead to significant improvement in tensile strength and elasticity. [ 6 ] It has previously been indicated in several works [ 9,52–53 ] that SiO 2 was mainly distributed around the EPDM particles or at the interface between PP and EPDM. After adding SiO 2 , the rubber particles were more compact (Figure 5C,D).…”

“…Composites are commonly produced by blending the reinforcing components and matrix under certain conditions, in which the particle‐reinforced fillers are most frequently utilized. [ 9–13 ] There are many factors that affect the reinforcement effect of fillers. [ 13–15 ] By employing thermodynamic and kinetic factors, particles can be regulated to disperse into rubber or plastic phase of composites, which plays a significant role in reinforcing the material.…”

Development of Toughened Flax Fiber Reinforced Composites. Modification of Poly(lactic acid)/Poly(butylene adipate-co-terephthalate) Blends by Reactive Extrusion Process

“…The most common preparation process of this type of material involves reactive blending, which improves the compatibility of the elastomer phase with the polymer matrix. This kind of solution were used also for PLA-based materials, where EBA-GMA [ 28 , 29 , 30 , 31 ], EMA-GMA [ 32 , 33 , 34 ] or natural rubber [ 35 , 36 , 37 , 38 ] was used. Unfortunately, beside the effectiveness of this approach the addition of non-degradable petroleum-based cannot be consider as sustainable solution, which is the reason for development of new methods involving blending PLA with other elastomeric or soft biopolymers.…”