Improvement of the Structure and Physicochemical Properties of Polylactic Acid Films by Addition of Glycero-(9,10-trioxolane)-Trialeate

Abstract

Glycero-(9,10-trioxolane)-trioleate (ozonide of oleic acid triglyceride, OTOA) was introduced into polylactic acid (PLA) films in amounts of 5, 10, 30, 50, and 70% w/w. The morphological, mechanical, thermal, and water absorption properties of PLA films after the OTOA addition were studied. The morphological analysis of the films showed that the addition of OTOA increased the diameter of PLA spherulites and, as a consequence, increased the proportion of amorphous regions in PLA films. A study of the thermodynamic properties of PLA films by differential scanning calorimetry (DSC) demonstrated a decrease in the glass transition temperature of the films with an increase in the OTOA content. According to DSC and XRD data, the degree of crystallinity of the PLA films showed a tendency to decrease with an increase in the OTOA content in the films, which could be accounted for the plasticizing effect of OTOA. The PLA film with 10% OTOA content was characterized by good smoothness, hydrophobicity, and optimal mechanical properties. Thus, while maintaining high tensile strength of 21 MPa, PLA film with 10% OTOA showed increased elasticity with 26% relative elongation at break, as compared to the 2.7% relative elongation for pristine PLA material. In addition, DMA method showed that PLA film with 10% OTOA exhibits increased strength characteristics in the dynamic load mode. The resulting film materials based on optimized PLA/OTOA compositions could be used in various packaging and biomedical applications.

Structure and Thermomechanical Properties of Polyvinylidene Fluoride Film with Transparent Indium Tin Oxide Electrodes

“…Thermal and physical-mechanical studies of PVDF film were performed by analogy with the studies of polylactic acid films, which we conducted earlier in [ 23 ].…”

A Novel Approach for Glycero-(9,10-trioxolane)-Trialeate Incorporation into Poly(lactic acid)/Poly(ɛ-caprolactone) Blends for Biomedicine and Packaging

“…To obtain film materials, NatureWorks ® Ingeo™ 3801X Injection Grade PLA (SONGHAN Plastics Technology Co., Ltd., Shanghai, China) with a viscosity-average molecular weight of 1.9 × 10 5 g/mol was used; PCL was used (SONGHAN Plastics Technology Co., Ltd., Shanghai, China) with a molecular weight of 90,000 ( Figure 1 ). Solutions were prepared using ≥99.5% dry purified chloroform (Sigma-Aldrich Inc., St. Louis, MO, USA); Glycero-(9,10-trioxolane)-trioleate (oleic acid triglyceride ozonide (OTOA)) was provided by Medozon (Moscow, Russia), and its chemical structure was described previously [ 17 , 18 ]. All reagents were used as received.…”

“…Deconvolution of complex DSC peaks was performed using NETZSCH Peak Separation 2006.01 program (NETZSCH-Gerätebau GmbH, Selb, Germany) employing the Fraser-Suzuki algorithm for asymmetric DSC curves [ 17 , 20 , 21 ].…”

“…XRD patterns of the PLA/PCL blend films were obtained using DRON-3M X-ray diffractometer (Bourevestnik, St. Petersburg, Russia) as described previously [ 17 ]. Relative crystallinity was estimated as χ = I C /(I C + I A ), where I C and I A are the integral intensities corresponding to the respective crystalline and amorphous phases [ 22 , 23 ].…”

“…OTOA is non-toxic, biocompatible, has good biodegradability and antimicrobial activity. In recent studies [ 17 , 18 ], it has been already shown that the introduction of OTOA into PLA fibers and films led to improvement in the physicochemical properties of the material. We have now obtained novel film materials based on a PLA/PCL blend with the addition of various amounts of OTOA (0–40 wt %) as a modifier.…”