Application of Degradable Elastic Polymers for Spunmelt Nonwoven Fabrics

Spunbond or spunmelt nonwoven materials are widely used in areas of medication and hygiene. The use of elastic spunmelt nonwovens has grown rapidly, among which degradable elastic nonwovens have turned into ideal raw fabrics for masks, protective clothing, and disposable sanitary products due to their good degradability and excellent mechanical properties. In particular, with the growing of the aging population, the demand for degradable elastic spunmelt nonwoven materials has further increased.

Biodegradable polymers are defined as "materials that can undergo chemical, biological or physical effects to generate carbon dioxide, water and biomass under the action of microorganisms such as bacteria, fungi, and algae". The degradation mechanisms mainly include biodegradation, photodegradation, thermal degradation, and solvent degradation. After being discarded, these materials can be decomposed and consumed by microorganisms as nutrients, or macromolecules can be depolymerized and broken into small molecular polymers with smaller molecular weights under physical conditions such as light and heat, and finally generate carbon dioxide and water through metabolism of microorganisms such as bacteria, fungi, and algae or others.

Nonwovens made from petroleum-based polymers, of which most are the cases, do not meet the demands of long-term development. As a result, the research of biodegradable nonwoven fabrics has become a hot spot. The performance of degradable elastic spunmelt nonwovens can be improved in many ways, starting from raw chips, processing techniques and after-treatment. Future development may focus on the use of elastic polymer resins (such as polyurethane) or high-crimp filament chips, as well as the modification of PLA. Some research results are as follows:

1) Firstly, prepare mixture of polyethylene glycol and elastic TPU materials; then blend PLA, with the mixture; lastly add PLA chips into the above blended materials. The final mixture made in the three steps is then used to produce degradable elastic spunmelt nonwovens.

2) Resins such as PLA and polycaprolactone, together with modified tourmaline, toughening agent, nucleator, etc., are suitable for producing degradable melt-blown nonwoven fabrics for masks with good toughness and filtration performance.

3) Produce spunbond nonwovens with PLA modified with polyamide elastomer.

4) Spinning parameters such as speed, temperature, pressure, and distance have a significant impact on the linear density, air permeability, and filtration properties of PLA-based meltblown materials..