1. Research on weather resistance test standards for TPU aprons

Abstract: In a climate simulation laboratory with temperature control accuracy of ±0.5℃ and humidity fluctuation of ±3%RH, multi-environment coupled aging tests were conducted on thermoplastic polyurethane (TPU) materials. Through a three-stage accelerated aging program (ASTM G154 UV cycle, ISO 4892-2 xenon lamp test and dynamic mechanical analysis), it was found that after 2000 hours of extreme environment (-30℃ to 80℃/RH 20%-95%/0.68W/m²@340nm UV) testing, the mechanical properties of TPU samples containing 2% hindered amine light stabilizers remained excellent (tensile strength retention rate 92%, elongation at break attenuation ≤8%), significantly exceeding the EN 343 protective clothing standard.

2. Digital upgrade of apron laser cutting process

Abstract: The digital twin model built based on the production data of the medical device factory shows that the use of the TRUMPF TruLaser 5030 system (4kW CO₂ laser) with visual positioning compensation can achieve a cutting accuracy of ±0.1mm (5 times higher than the traditional process) and a processing speed of 8m/min. The genetic algorithm optimized nesting scheme integrated with the TensorFlow framework increased the utilization rate of TPU coils from 74% to 89%. Practical application shows that a factory with an annual output of 500,000 aprons can save 37 tons of raw materials (equivalent to US$180,000) per year, shorten the equipment investment recovery period to 14 months, and achieve a product qualification rate of 99.6%.

3. Development of food-grade apron composite antibacterial coating

Abstract: The nano-silver ion coating (50nm particle size/0.8% loading) and titanium dioxide coating (20nm particle size/92% anatase phase) prepared by the magnetron sputtering-spraying composite method both show excellent antibacterial properties. The former inactivates 99.2% of E. coli through charge adsorption in 30 minutes, and the latter has an antibacterial rate of >90% under visible light for 72 hours. After FDA migration test (3% acetic acid/50% ethanol) and 10 cycles of 82℃ industrial dishwasher, the two coatings have excellent chemical stability (migration amount <0.03mg/kg), helping catering companies to extend the apron replacement cycle to 21 days.

4. Comparative study of apron seam strengthening processes

Abstract: Multi-physics field coupling experiments show that 180℃/0.6MPa hot pressing welding can form a 120μm fusion zone (peel strength 45N/cm), while 20kHz high-frequency ultrasonic sewing efficiency is increased by 40% and is suitable for three-dimensional sewing. The innovative gradient pressurization process (0.2-0.8MPa step loading) makes the seam crystallinity reach 27%, and the strength retention rate after 5000 bending tests is 91%, which fully meets the requirements of EN ISO 13935-2 standard.

5. Closed-loop production system for recycled TPU aprons

Abstract: The molecular weight distribution index (PDI) of recycled TPU produced by the three-stage recycling process (waste crushing and purification → ethylene glycol depolymerization → MDI chain extension and repolymerization) is optimized from 1.8 to 1.3. Life cycle assessment shows that each apron reduces CO₂eq emissions by 2.1kg (a decrease of 38%), and an annual production of 2 million pieces can save 4,600 tons of petroleum-based raw materials. Its 85% post-consumer recycled content is UL 2809 certified.