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[EN] Mater-Bi(R) NF866 (MB) was blended with gum rosin and two pentaerythritol esters of gum rosin (labeled as LF and UT), as additives, to produce biobased and compostable films for food packaging or agricultural mulch films. The films were prepared by blending MB with 5, 10, and 15 wt.% of each additive. The obtained films were characterized by optical, colorimetric, wettability, and oxygen barrier properties. Moreover, the additives and the MB-based films were disintegrated under composting conditions and the effect of each additive on the biodegradation rate was studied. All films were homogeneous and optically transparent. The color of the films tended to yellow tones due to the addition of pine resin derivatives. All the formulated films presented a complete UV-transmittance blocking effect in the UVA and UVB region, and those with 5 wt.% of pine resin derivatives increased the MB hydrophobicity. Low amounts of resins tend to maintain the oxygen transmission rate (OTR) values of the neat MB, due to its good solubilizing and compatibilizing effects. The disintegration under composting conditions test revealed that gum rosin completely disintegrates in about 90 days, while UT degrades 80% and LF degrades 5%, over 180 days of incubation. As expected, the same tendency was obtained for the disintegration of the studied films, although Mater-Bi(R) reach 28% of disintegrability over the 180 days of the composting test.

[EN] Completely biobased and biodegradable thermoplastic starch (TPS) based materials with a tunable performance were prepared for food packaging applications. Five blends were prepared by blending TPS with 10 wt%. of different pine resins derivatives: gum rosin (GR), disproportionated gum rosin (RD), maleic anhydride-modified gum rosin (CM), pentaerythritol ester of gum rosin (LF), and glycerol ester of gum rosin (UG). The materials were characterized in terms of thermo-mechanical behavior, surface wettability, color performance, water absorption, X-ray diffraction pattern, and disintegration under composting conditions. It was determined that pine resin derivatives increase the hydrophobicity of TPS and also increase the elastic component of TPS which stiffen the TPS structure. The water uptake study revealed that GR and LF were able to decrease the water absorption of TPS, while the rest of the resins kept the water uptake ability. X-ray diffraction analyses revealed that GR, CM, and RD restrain the aging of TPS after 24 months of aging. Finally, all TPS-resin blends were disintegrated under composting conditions during the thermophilic incubation period (90 days). Because of the TPS-resin blend's performance, the prepared materials are suitable for biodegradable rigid food packaging applications.

[EN] The present study aims to investigate the effects of gum rosin (GR) microspheres coating over the hydrophobicity of the outer layer of a polypropylene (PP) based surgical face mask. The gum rosin coating was deposited over the surface of the face mask outer layer by electrospraying technique. The deposition of GR microspheres was confirmed by field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR) analysis. The thermal analysis determined a cooperative effect between the microspheres and the mask fibre to increase the maximum degradation rate temperature and the onset degradation temperature. To follow the effect of the GR microspheres coating over the hydrophobicity of the surgical face mask, FESEM and wettability analyses were conducted before and after 3, 6, and 9 h of wearing time. In the FESEM image, it was seen that the microsphere was homogeneously distributed over the nonwoven fibre and its presence increases the roughness of the fibres due to the bulge of microspheres. The wettability measurements suggest that the microspheres coating helps to keep the original hydrophobicity of the outer layer of the surgical face mask even after 6 h of wearing time. Indeed, after 9 h of wearing time, the water contact angle (WCA) of the GR coated face mask is higher than the WCA of the surgical face mask without the coating at 3 h of wearing time. Therefore, the gun rosin microspheres coating improved the hydrophobicity of the surgical face mask which may allow improved protection and/or extended lifetime of use.

[EN] Gum rosin (GR) was used as a natural additive to improve the compatibility between polylactic acid, PLA, and poly(butylene adipate-co-terephthalate, PBAT, blended with 20 wt.% of PBAT (PLA/PBAT). The PBAT was used as a soft component to increase the ductility of PLA and its fracture toughness. The coalescence of the PBAT domains was possible due to the plasticization effect of the GR component. These domains contributed to increasing the toughness of the final material due to the variation and control of the PBAT domains' size and consequently, reducing the stress concentration points. The GR was used in contents of 5, 10, 15, and 20 phr. Consequently, the flexural properties were improved and the impact resistance increased up to 80% in PLA/PBAT_15GR with respect to the PLA/PBAT formulation. Field emission scanning electron microscope (FESEM) images allowed observing that the size of PBAT domains of 2-3 mu m was optimal to reduce the impact stress. Differential scanning calorimetry (DSC) analysis showed a reduction of up to 8 degrees C on the PLA melting temperature and up to 5.3 degrees C of the PLA glass transition temperature in the PLA/PBAT_20GR formulation, which indicates an improvement in the processability of PLA. Finally, transparent films with improved oxygen barrier performance and increased hydrophobicity were obtained suggesting the potential interest of these blends for the food packaging industry

[EN] In this work, the presence of biodegradable polymers in recycled plastic materials was characterized using readily available techniques. Recycled polypropylene (PP), polystyrene (PS) and polyethylene terephthalate (PET) were studied. The contamination of these plastics with polylactic acid (PLA), polyhydroxybutyrate (PHB) and thermoplastic starch (TPS) was simulated using 10 wt.% of the contaminant. Fourier transform infrared spectrometry (FTIR) and differential scanning calorimetry (DSC) were used as characterization techniques. In addition, the effect of aging on recycled products from PET blends contaminated with TPS and PHB was studied. The results show changes in the intensity of the FTIR spectra bands of the PS and PP blends contaminated with biodegradable polymers. By DSC, changes in the cold crystallization peak of recycled PET are observed when mixed with TPS and PHB. When the contaminant is PLA, the changes are masked due to the thermal characteristics of both materials. In PS, changes in the calorimetric curves are identified by the presence of PLA and PHB. Contamination with PLA, PHB and TPS hinders the processing of recycled PET after one year of storage due to the aging of the material.

"This is the peer reviewed version of the following article: De La Rosa-Ramírez, Harrison, Miguel Aldas, José Miguel Ferri, Juan López-Martínez, and María Dolores Samper. 2020. "Modification of Poly (Lactic Acid) through the Incorporation of Gum Rosin and Gum Rosin Derivative: Mechanical Performance and Hydrophobicity." Journal of Applied Polymer Science 137 (44). Wiley: 49346. doi:10.1002/app.49346, which has been published in final form at https://doi.org/10.1002/app.49346. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.", [EN] The modification of PLA by melt compound with gum rosin (GR) and pentaerythritol ester of GR (PEGR) was investigated by studying the mechanical and thermal performance, blends morphology, wettability, and water absorption. Standard testing specimens for characterization were made at a variate resin content of 5, 10, and 15 part per hundred resin (phr) and manufactured by injection molding. It was found that GR and PEGR had a lubricating effect in PLA polymeric chains, resulting in a remarkable increase of 790 and 193% in melt flow index with only 5 phr GR and PEGR contents, respectively. A significant change in more than 10 degrees of increasing water contact angle was observed for PLA with 15 phr PEGR. Thermogravimetric analysis reveals that PEGR led to delayed PLA degradation/decomposition process to higher temperature, increasing the onset temperature (T-5%) in more than 7 degrees C for PLA with 15 phr PEGR.