Supertough Polylactide Materials Prepared through In Situ Reactive Blending with PEG-Based Diacrylate Monomer

Abstract

Supertough biocompatible and biodegradable polylactide materials were fabricated by applying a novel and facile method involving reactive blending of polylactide (PLA) and poly(ethylene glycol) diacylate (PEGDA) monomer with no addition of exogenous radical initiators. Torque analysis and FT-IR spectra confirm that cross-linking reaction of acylate groups occurs in the melt blending process according to the free radical polymerization mechanism. The results from differential scanning calorimetry, phase contrast optical microscopy and transmission electron microscopy indicate that the in situ polymerization of PEGDA leads to a phase separated morphology with cross-linked PEGDA (CPEGDA) as the dispersed particle phase domains and PLA matrix as the continuous phase, which leads to increasing viscosity and elasticity with increasing CPEGDA content and a rheological percolation CPEGDA content of 15 wt %. Mechanical properties of the PLA materials are improved significantly, for example, exhibiting improvements by a factor of 20 in tensile toughness and a factor of 26 in notched Izod impact strength at the optimum CPEGDA content. The improvement of toughness in PLA/CPEGDA blends is ascribed to the jointly contributions of crazing and shear yielding during deformation. The toughening strategy in fabricating supertoughened PLA materials in this work is accomplished using biocompatible PEG-based polymer as the toughening modifier with no toxic radical initiators involved in the processing, which has a potential for biomedical applications.

Fully bio-based, highly toughened and heat-resistant poly(L-lactide) ternary blends via dynamic vulcanization with poly(D-lactide) and unsaturated bioelastomer

“…Dynamic vulcanization, involving selective crosslinking of rubber polymer during melt blending with a thermoplastic polymer, has been demonstrated to be a powerful technique to control the morphology, enhance interfacial adhesion, and improve the final properties of PLLA blends with elastic polymers [19][20][21][22][23]. Some supertough PLLA blends with impact strengths of more than 530 J m −1 (or 53 kJ m −2 ) have been achieved by dynamic vulcanization of PLLA with some elastic polymers [22,[24][25][26][27][28]. It is worth noting that the sustainability of PLLA was compromised since most elastic polymers in previous studies were prepared from non-renewable feedstocks [19,25,28,29].…”

“…Some supertough PLLA blends with impact strengths of more than 530 J m −1 (or 53 kJ m −2 ) have been achieved by dynamic vulcanization of PLLA with some elastic polymers [22,[24][25][26][27][28]. It is worth noting that the sustainability of PLLA was compromised since most elastic polymers in previous studies were prepared from non-renewable feedstocks [19,25,28,29]. In this sense, some sustainable elastomers such as natural rubber, epoxidized natural rubber, and bioelastomer have gained much attention in fabricating fully sustainable supertough PLLA via dynamic vulcanization [22,24,30,31].…”

Improvements in mechanical strength and thermal stability of injection and compression molded components based on Poly Lactic Acids

“…[1] In this way, intervening on the structure and morphology of the resulting blends (formation of dispersed phases structures [2][3][4][5][6][7][8] or interconnected and co-continuous structures [9][10][11][12] ); it is possible to obtain materials boasting higher mechanical strength and ductility. On the other hand, PLA shows a molten phase that is not thermally resistant during conventional | 2159 AVERSA Et Al.…”

Polyethyleneglycol diacrylate hydrogels with plasmonic gold nanospheres incorporated via functional group optimization

“…Similarly, strong peaks at the wavenumber of 1732 and 2882 cm −1 observed correspond to -C=O stretching from ester bonds and C-H stretching vibrations, respectively [21]. The band at 1635 cm −1 corresponds to the reaction product of OH − which comes from H 2 O and oxidized products of citrate produced during the Au 3+ reduction [13,22]. Figure 6b shows that the interactions of Au with PEG-DA were confirmed by presence of intense absorption bands at 1732 and 2882 cm −1 with their difference in intensity after functionalization process and dispersion in the PEG-DA matrix [23].…”

“…In this context, PEG-DA based materials had shown very promising applications by preparing highly stable hydrogels which were used as mechanical sensors, piezo actuating devices, stimuli response materials and so on [12]. Moreover, polyethyleneglycol diacrylate (PEG-DA) is non-volatile, non-toxic, environmentally benign and tailor made into various shapes, enabling to act as potential stabilizers and matrices for the formation of functional hydrogels [13]. In this paper, a facile method was demonstrated to incorporate functionalized Au nanospheres into PEG-DA polymer matrices by an ex situ approach for the preparation of hybrid Au/PEG-DA hydrogels to further accelerate applications based on PEG-DA and Au hybrids.…”