Grafted Lactic Acid Oligomers on Lignocellulosic Filler towards Biocomposites
| Autor: | Anna Czajka, Radosław Bulski, Anna Iuliano, Andrzej Plichta, Kamila Mizera, Joanna Ryszkowska |
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| Rok vydání: | 2022 |
| Předmět: |
Technology
Microscopy QC120-168.85 biodegradable composites lignocellulosic material in situ polymerization QH201-278.5 chemical modification poly(lactic acid) composites grafting biocomposites Engineering (General). Civil engineering (General) Article TK1-9971 Descriptive and experimental mechanics General Materials Science Electrical engineering. Electronics. Nuclear engineering TA1-2040 |
| Zdroj: | Materials; Volume 15; Issue 1; Pages: 314 Materials, Vol 15, Iss 314, p 314 (2022) Materials |
| ISSN: | 1996-1944 |
| DOI: | 10.3390/ma15010314 |
| Popis: | Lactic acid oligomers (OLAs) were in situ synthesized from lactic acid (LAc) and grafted onto chokeberry pomace (CP) particleboards by direct condensation. Biocomposites of poly (lactic acid) (PLA) and modified/unmodified CP particles containing different size fractions were obtained using a mini-extruder. To confirm the results of the grafting process, the FTIR spectra of filler particles were obtained. Performing 1HNMR spectroscopy allowed us to determine the chemical structure of synthesized OLAs. The thermal degradation of modified CP and biocomposites were studied using TGA, and the thermal characteristics of biocomposites were investigated using DSC. In order to analyse the adhesion between filler particles and PLA in biocomposites, SEM images of brittle fracture surfaces were registered. The mechanical properties of biocomposites were studied using a tensile testing machine. FTIR and 1HNMR analysis confirmed the successful grafting process of OLAs. The modified filler particles exhibited a better connection with hydrophobic PLA matrix alongside improved mechanical properties than the biocomposites with unmodified filler particles. Moreover, a DSC analysis of the biocomposites with modified CP showed a reduction in glass temperature on average by 9 °C compared to neat PLA. It confirms the plasticizing effect of grafted and ungrafted OLAs. The results are promising, and can contribute to increasing the use of agri-food lignocellulosic residue in manufacturing biodegradable packaging. |
| Databáze: | OpenAIRE |
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