The Application of PLA Resin on Nonwovens Production

Abstract

Poly (lactic acid) (PLA) as a thermoplastic and biodegradable material holds good prospect in medical, agricultural, apparel, upholstery, hygiene, and other applications in the form of fiber. Among them, the nonwoven produced with PLA fiber is one of the most important forms. In this paper, the biodegradable properties of PLA fiber were reviewed. Moreover, some manufacturing processes of the biodegradable PLA product, such as spunlaced, spunbonded thermal, spunbonded needle punched, melt-blown were also summarized. It also draws some conclusions about the current problems and the prospect.

Effect of Simulated Weathering on Physicochemical Properties and Inherent Biodegradation of PLA/PHA Nonwoven Mulches

“…MB nonwovens are manufactured by forcing a thermoplastic polymer melt through an extruder dye. First-generation MB-PLA mulch prepared by us underwent an 85 % decrease of tensile strength when buried in compost-and lime-augmented soils for a 10 week greenhouse incubation period, thereby reflecting the initial stages of biodegradation [23][24][25][26][27]. More recent greenhouse soil burial studies demonstrate that the incorporation of PHA into PLA-based nonwoven mulches enhanced biodegradation (Dharmalingam et al, submitted).…”

“…1) [23]. Nonwovens are sheets, webs, or bats of randomly-oriented micron-sized fibers that are bonded together physically or chemically [23][24][25][26][27]. The molecular structure of the two polymers is also given in Fig.…”

“…SB (spunmelt) nonwovens are prepared in a continuous process consisting of extrusion and spinning of a polymer melt, collection of the fibers on a conveyor belt, followed by heat bonding, and are comprised of strong, thermally point-bonded webs of continuous filaments with fiber diameters of 12-15 lm [23][24][25][26][27]. SB mulches have been shown to be robust for long-term agricultural uses, undergoing minimal deterioration during recently conducted 28-month and 30-week soil burial studies [23,34] and in field studies conducted in Tennessee, Texas, and Washington [35][36][37].…”

Soil Degradation of Polylactic Acid/Polyhydroxyalkanoate-Based Nonwoven Mulches

“…PLA was selected as the major nonwoven (biobased) feedstock because of its relatively low cost (2.10 USD kg -1 ), abundance, high mechanical strength [8,31,32], and frequent use in nonwovens [28]. However, PLA also possesses undesirable attributes: high crystallinity and brittleness, and slow biodegradability under ambient soil conditions [8,32] (although PLA biodegrades under composting conditions, e.g.…”

“…Motivated by this need, the authors [25] have prepared mulches from PLA and blends of PLA and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (the latter referred to as polyhydroxyalkanoate, or PHA, herein) using spunmelt and meltblown nonwovens textile processes. Nonwovens are sheets, webs, or bats of randomly-oriented fibers of diameter 5-20 lm that are bonded together by several means [26][27][28][29][30]. Spunbonded (SB) nonwovens are produced by a continuous process consisting of extrusion and spinning of a polymer melt, where it undergoes warm air drag attenuation, collection of the resultant fibers on a porous conveyor belt, followed by bonding (e.g., via heat), yielding webs possessing relatively large fibers that are more strongly oriented in the lengthwise (machine) direction, hence possessing a high tensile strength per unit mass.…”