Preparation and characterization of poly(l-lactic acid)/TiO2 nanoparticle nanocomposite films with high transparency and efficient photodegradability

Influence of accelerated ageing on the physico-mechanical properties of alkali-treated industrial hemp fibre reinforced poly(lactic acid) (PLA) composites

“…The glass transition temperature was found to decrease from about 61 o C to about 42 and 45 o C, and melt temperature was found to decrease from about 148 o C, to about 140 and 144 o C for AUL and AAL composites respectively. The depression of the glass transition and melt temperature by photodegradation of PLA has also been observed by other researchers [17,33]. The shoulder in the endothermic melting peak was found to disappear for AAL composite while the shoulder was found to merge for AUL composite after accelerated aging of 1000 hours.…”

“…The bands at 1734 and 1600 cm -1 are characteristic absorptions of carbonyl stretching vibrations of non-conjugated (in xylan) and conjugated (in lignin) esters and carboxylic acids, and their concentration increases as carbonyl groups are liberated from lignin and/or carbohydrates due to chemical degradation [30][31][32]. Pure PLA has a C-H deformation band at 1350 to 1460 cm -1 , which was found to be at 1400 cm -1 for both control and accelerated aged samples [17]. Figure 10 shows the WAXRD patterns for AUL and AAL composites after 1000 hours accelerated ageing.…”

“…The formed singlet oxygen is a source of peroxides [14], which can initiate the auto-oxidation of carbohydrates and cleavage of lignin [15,16]. In polylactic acid (PLA) matrix the active oxygen species initiate the degradation reaction by attacking neighbouring PLA chain and the degradation process extends into the PLA through the diffusion of these reactive oxygen species [17].…”

Influence of TiO2Nanoparticle Filler on the Properties of PET and PLA Nanocomposites

“…16 Table 1 shows that the reduction of T g for PET nanocomposites with increasing TiO 2 content is not very significant. Todorov et al 13,17 The incorporation of nanoparticles could disturb the packing and regularity of polymer chains and cause free volume increment in a system. This effect could be more significant at higher nanoparticle contents, when more agglomerations form in the matrix.…”

“…Among many different types of nano sized fillers, TiO 2 nano powder is increasingly being investigated because it is non-toxic, chemically inert, has broadband UV filter properties, is anti bacterial from its photoirradiation effect, corrosion resistant and has high level hardness, high refractive index and low cost. 7 The effects of nano sized TiO 2 on crystallization and the viscoelastic behaviour of synthetic [8][9][10] and natural [11][12][13] polymers have been discussed in some other research. Depending on the polymeric matrix type, the addition of TiO 2 nanoparticles could increase 8 or decrease 12,13 the degree of crystallinity of nanocomposites.…”