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Core–shell structured particles have been used to toughen brittle polylactide (PLA) extensively. In this research, reactive core–shell (RCS) particles with polybutadiene (PB) as core and the terpolymer styrene–acrylonitrile‐glycidyl methacrylate as shell were prepared to improve the toughening ability of RCS for PLA. The tert‐dodecyl mercaptan (TDDM) content was varied during polymerization and higher TDDM concentrations induced lower grafting and cross‐linking of the PB phase, which significantly influenced the dispersed phase morphology and toughness of RCS toughened PLA blends. With the increase of TDDM content, the phase morphology of RCS changed from uniform dispersion, net‐like structure to an agglomeration pattern. The impact strength of PLA blends increased with TDDM content and reached 922 J/m for the PLA/RCS‐T5 (TDDM: 1.18 wt%), which was 30 times higher than pristine PLA and ~3 times than PLA/RCS‐T0 blend. Higher TDDM contents decreased toughening efficiency. Appropriate TDDM contents decreased the glass transition temperature (Tg) and cross‐linking degree of RCS particles which enhanced the cavitation ability of the PB core phase and promoted the shear yielding of PLA matrix. The modification effect of TDDM solves the problem of insufficient toughening ability of core–shell particles. Under the same toughener content, the modified RCS particles make the PLA blend achieve super toughness. [ABSTRACT FROM AUTHOR]

An epoxy macromolecular chain extender, polymethyl methacrylate-co-glycidyl methacrylate (PMMA-co-GMA), was synthesized by continuous random free radical polymerization, which was introduced into poly(ethylene terephthalate) (PET) and PET blends. The modified PET blends exhibited higher torque with increasing the content and the polymerization degree of PMMA-co-GMA. The rise of torque after initial melting period was observed, which indicated the occurrence of reaction between the epoxy group of PMMA-co-GMA and hydroxyl or carboxyl end groups of PET. The melting temperature, crystallization temperature, and crystallization degree of PET blends decreased. The chain extender was introduced in PET/ethylene–propylene–diene monomer (EPDM)-graft-GMA (EPDM-g-GMA) blends with the composition of 85/15, which exhibited brittle fracture behavior. The blends, in which the chain extender content in PET was over 8 wt%, exhibited ductile fracture behavior. EPDM-g-GMA was used to toughen PET with 8 wt% chain extender. The brittle–ductile transition took place between the rubber content of 10 wt% and 15 wt%. The transition was in advance when compared with PET/EPDM-g-GMA blends. The content of chain extender in PET showed little influence on the compatibility of PET blends. The macromolecular chain extender was an effective extender for PET. The introduction of macromolecular chain extender showed contribution for the toughening PET. [ABSTRACT FROM AUTHOR]

Butadiene glycidyl methacrylate-functionalized-methyl methacrylate (PB-g-MG) core–shell copolymer was used to toughen poly(butylene terephthalate) (PBT). Fourier transform infrared (FTIR) spectra and torque tests showed that compatibilization reactions took place between the carboxyl and/or hydroxyl groups of PBT and the epoxy groups of PB-g-MG. Phase morphology results showed that the PB-g-MG core–shell particles dispersed in the PBT matrix uniformly. The addition of PB-g-MG significantly improved the mechanical properties of PBT. The elongation at break and the impact strength increased with the increase of PB-g-MG content. SEM results showed that the shear yielding properties of the PBT matrix was the main toughening mechanism. The relationship between complex viscosity and angular frequency of the PBT/PB-g-MG blends indicated that the melt viscosity was higher than that of pure PBT. [ABSTRACT FROM AUTHOR]

Glycidyl methacrylate-functionalized methyl methacrylate-butadiene ( MB- g- GMA) copolymers were prepared via an emulsion polymerization process. These functionalized copolymers were blended with polylactide ( PLA). Dynamic mechanical analysis and differential scanning calorimetry results showed that the addition of MB- g- GMA did not result in a marked change in the glass transition temperature of PLA. With an increase of MB- g- GMA content, the tensile strength of the blends decreased; however, the elongation at break and impact strength increased significantly. From scanning electron micrographs, there was large plastic deformation (shear yielding) in blends subjected to impact tests, which was an important energy-dissipation process and led to a toughened polymer. Rheological investigation demonstrated that there was a significant dependence of viscosity on composition. When the MB- g- GMA content increased, the viscosity began to increase. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Ethylene-propylene-diene elastomer (EPDM), which was grafted with glycidyl methacrylate (GMA) by reactive blending, was used as modifier to toughen poly(ethylene terephthalate) (PET) and enhance the compatibility of PET/EPDM blends. Mechanical properties showed that brittle ductile transition was observed in PET/EPDM-g-GMA blends with the rubber content over 20 wt.%. The introduction of EPDM-g-GMA increased the mechanical properties of the PET/EPDM blends and decreased the particle size of EPDM dispersed phase. DSC analysis showed that the introduction of EPDM-g-GMA made the crystallization of PET difficult. DMA results showed that the compatibility of PET and EPDM phase was improved by EPDM-g-GMA. [ABSTRACT FROM AUTHOR]

Glycidyl methacylate functionalized acrylonitrile–butadiene–styrene particles (ABS-g-GMA) prepared via an emulsion polymerization method were used to toughen poly(butylene terephthalate) (PBT)/bisphenol A polycarbonate (PC) blends. DMA results showed PBT was partially miscible with PC and the addition of ABS-g-GMA improved the miscibility between PBT and PC. DSC tests further testified that the introduction of ABS-g-GMA improved the miscibility of PBT and PC according to the Tmdepression criterion. SEM displayed a very good dispersion of ABS-g-GMA particles in the PBT/PC blends and the dispersed phase size of PC decreased due to the compatibilization effect of ABS-g-GMA. The mechanical properties showed that the addition of 10 wt% ABS-g-GMA was sufficient to induce a super-tough fracture behavior to the PBT/PC blends and a notched impact strength of more than 1000J/m was achieved. The Vu-Khanh test showed that stable crack propagation took place for PBT/PC blends with the addition of ABS-g-GMA and led to ductile failure. [ABSTRACT FROM PUBLISHER]

Functional catalytic hydrogels were a promising catalyst carrier with the advantages of low cost, high efficiency and environmental friendliness. However, conventional hydrogels suffered from mechanical defects and brittleness. Acrylamide (AM) and lauryl methacrylate (LMA) were used as raw materials, SiO 2 -NH 2 spheres as toughening agents, and chitosan (CS) as stabilizers to form hydrophobic binding networks. p(AM/LMA)/SiO 2 -NH 2 /CS hydrogels exhibited superior stretchability and withstood strains up to 14,000 %. In addition, these hydrogels exhibited exceptional mechanical properties, including a tensile strength of 213 kPa and a toughness of 13.1 MJ/m3. Surprisingly, the introduction of chitosan into hydrogels showed excellent antibacterial activity against S. aureus and E. coli. At the same time, the hydrogel served as a template for the formation of Au nanoparticles. This resulted in high catalytic activity for methylene blue (MB) and Congo red (CR) on p(AM/LMA)/SiO 2 -NH 2 /CS-8 %-Au hydrogels with K app of 1.038 and 0.76 min−1, respectively. The catalyst was also found to be reusable for 10 cycles while maintaining an efficiency of over 90 %. Therefore, innovative design strategies can be used to develop durable and scalable hydrogel materials for catalysis in the wastewater treatment industry. • A novel hydrogel encapsulation method for immobilizing metal nanoparticles and its application in industrial sustainable catalysis. • Hydrogels can be used as carriers to load Au nanoparticles and effectively prevent their agglomeration. • Hydrogel catalysts have high catalytic activity and reusability for dye reduction. [ABSTRACT FROM AUTHOR]