Mechanická recyklace kompozitu kyseliny poly(L-mléčné) s kávovou sedlinou
Loading...
Date
2021-11-30
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Diplomová práce se zabývá hodnocením vlivu opakované mechanické recyklace na vlastnosti kompozitu kyseliny polymléčné (PLLA) s 10 % kávové sedliny (KS). Pro experimentální měření jsou zhotoveny výstřiky kompozitu PLLA/KS ze sedmi recyklačních cyklů. Hodnoceny jsou reologické, termické, mechanické vlastnosti a nadmolekulární struktura před a po odstranění tepelné historie materiálu. Vlastnosti a struktura kompozitu jsou také vystaveny účinku umělého klimatického stárnutí pro posouzení použitelnosti v praxi. Výzkum prokázal nukleační efekt kávové sedliny a její pozitivní vliv na stabilitu užitných vlastností (modul pružnosti v tahu i ohybu, pevnost v tahu, rázová houževnatost) v průběhu mechanické recyklace. Ve studii bylo také zjištěno, že kávová sedlina způsobila zvýšení tažnosti. Během studie vlivu klimatického stárnutí kompozitu byl prokázán negativní vliv recyklátu u meze pevnosti v ohybu, tažnosti a rázové houževnatosti v průběhu životnosti dílu.
The diploma thesis deals with the evaluation of the effect of repeated mechanical recycling on the properties of polylactid acid (PLLA) composite with 10 % of spent coffee grounds (SCG). For the experimental measurements the PLLA/KS composite specimens are taken from seven recycling cycles. The reological, thermal, mechanical properties and supramolecular structure before and after removal of the thermal history of the material are evaluated. The properties and structure of the composite are also subjected to the effect of artificial climatic aging to assess the applicability in practice. The research demonstrated the nucleation effect of coffee grounds and its positive influence on the stability of the utility properties (tensile and flexural modulus, tensile strength, impact toughness) during mechanical recycling. The study also found that spent coffee grounds caused an increase in elongation in break. During the study of the effect of climatic ageing of the composite the negative effect of recyclate was shown for flexural strength, elongation in break and impact toughness during the service life of the product.
The diploma thesis deals with the evaluation of the effect of repeated mechanical recycling on the properties of polylactid acid (PLLA) composite with 10 % of spent coffee grounds (SCG). For the experimental measurements the PLLA/KS composite specimens are taken from seven recycling cycles. The reological, thermal, mechanical properties and supramolecular structure before and after removal of the thermal history of the material are evaluated. The properties and structure of the composite are also subjected to the effect of artificial climatic aging to assess the applicability in practice. The research demonstrated the nucleation effect of coffee grounds and its positive influence on the stability of the utility properties (tensile and flexural modulus, tensile strength, impact toughness) during mechanical recycling. The study also found that spent coffee grounds caused an increase in elongation in break. During the study of the effect of climatic ageing of the composite the negative effect of recyclate was shown for flexural strength, elongation in break and impact toughness during the service life of the product.
Description
Subject(s)
biokompozit, PLLA, kávová sedlina, mechanická recyklace, klimatické stárnutí, biocomposite, PLLA, spent coffee grounds, mechanical recycling, climatic ageing