Preparation of modified polylactic acid fiber containing anti‐hydrolysis agents

Abstract

Polylactic acid (PLA) is a promising alternative to petroleum‐based polymers due to its biodegradability. However, its low mechanical properties in the presence of moisture are a challenge for textile applications. In this study, we investigated the effects of two anti‐hydrolysis agents, an epoxy‐based agent (ADR) and an aromatic carbodiimide‐based agent (ZIKA), on the mechanical properties and hydrolysis resistance of PLA fibers. A melt‐spinning process was used to prepare anti‐hydrolysis fibers by adding 0.3 and 0.5 wt% of ADR and ZIKA to PLA. The topology of ADR/PLA and ZIKA/PLA was determined by Fourier transform infrared spectroscopy (FT‐IR). Analysis of the compound chip revealed that ADR formed a branched chain in PLA, while ZIKA produced a linear molecular structure. The hydrolysis resistance of the fibers was evaluated by analyzing their crystallinity, hydrothermal shrinkage behavior, morphology, and tensile strength. ZIKA/PLA fibers showed higher orientation and crystallinity than ADR/PLA fibers. After hydrolysis, the tensile strength of ADR 0.5%/PLA fibers decreased by 31%, while that of ZIKA 0.5%/PLA fibers decreased by only 5% due to the linear molecular structure of ZIKA/PLA. Our findings indicate that ZIKA is more effective than ADR in producing hydrolysis‐resistant PLA fibers with high crystallinity, orientation, and mechanical durability.

Enhancing the Hydrolytic Stability of Poly(lactic acid) Using Novel Stabilizer Combinations

“…Thus, the reduction of the number average molecular weight for the samples with 2.0% pCDI was only 25%. This is consistent with other studies in which carbodiimides were used for stabilization [ 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. In some cases, however, even lower molecular weight reductions were observed during hydrolytic aging [ 29 ].…”

“…One class of additives that reacts with moisture and the carboxyl end groups is defined as hydrolysis inhibitors. Primarily, carbodiimides are used here, which have already been studied many times in PLA [ 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. They are commercially available in various structural configurations (monomeric, polymeric, aliphatic, aromatic, cyclic).…”

“…However, it can be assumed that a stabilizing effect is only achieved in the case of a direct reaction with the moisture and the carboxyl groups. Additives that react only with the carboxyl end group, but not with moisture, e.g., epoxy-based additives, exhibit no effect [ 28 , 36 ]. Aziridines are known to react with water at elevated temperatures [ 37 , 38 ], but aziridine-based structures have, so far, only been investigated in PLA as crosslinkers for star or long-chain branching [ 39 ] but not for their effect on hydrolysis resistance.…”

Crystallization behaviors of chain extended poly (lactic acid) modified with ST-NAB3 and its improved mechanical and thermal properties

“…6, the crystallization rates of PLA systems were analyzed by examining the slope of the double-ln curves. It was observed that the slope of CPLA systems increased after the addition of HNA, which indicated an increase in crystallization rate [52]. Crystallization rate of PLA systems was analyzed according to half crystallization time (t 1/2 ).…”

Blend of Fibres to Improve the Mechanical Properties of Needle-Punched Nonwovens for PM2.5 Air Filtration

“…PET fibres offer high durability and are resistant to moisture, mildew, and most chemicals. PLA[58][59][60][61] fibres are derived from renewable resources, making them environmentally friendly. They offer good comfort, softness, and breathability.…”