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It has been the fifth month since the outbreak of COVID-19. The epidemic situation in Europe and the United States continues to be tense. The first-line medical protective equipment is in short supply, and the daily consumption of medical supplies is countless. In order to face the global disaster brought about by coronavirus, domestic and foreign manufacturers have cross-border assistance, hoping to help people get through this critical period.

However, compared with the general type of protective goods, the products for medical protection must be controlled by the established competent authority for different risk levels, including the quality management system audit at the manufacturing end and product technical review. At present, many countries have a consensus on the control of quality management system, and unanimously accept ISO 13485:2003 as the standard for manufacturers to establish quality management system. Product technology examination standards such as United States FDA or NIOSH standard product comparison, CE product hazard and risk control in the EU, and product performance test in Mainland China and the Russian Federation are more representative. No matter which country's examination standard is adopted, the quality of the protection products must be above the standard to ensure that the key users can minimize the virus to the greatest extent and fight the epidemic effectively.

Polyurethane resin (PU) has excellent biocompatibility and barrier properties, which is an indispensable part of medical textiles, and can be widely adapted to meet different demands. With the progress of industry, the production side actively research advanced technology to adapt to the rapid development of medical industry. Chen Yucheng, an industry analyst at the Taiwan Institute of Industry and Research, also said that PU will have an advantage over other materials in human life in the future. “CPMC has been deeply engaged in the production and development of PU materials with environmental protection, sustainable characteristics and multiple applications for more than three decades. Now it is facing the global spread of disease, the development and application of high molecular elastic polymers have also become one of the most important tasks of anti-epidemic.
 

A. Thermoplastic Polyurethane , TPU

The US Food and Drug Administration (FDA) estimate that there are currently 3,600 different medical devices and 2,800 diagnostic products. The environmentally friendly TPU is one of the most versatile plastic materials in the medical field, with resistance to gamma rays, oils, acids and alkalis, superior material properties, biocompatibility and ease of manufacture. It can bridge the gap between rubber and rigid thermoplastics, completely replace traditional PVC materials. Therefore, the most important parts in most of the medical equipment and related products can be made of TPU. The material properties can be adapted by using different polyol formulations. The following are examples of related applications of various types of TPU in epidemic prevention or professional medical supplies:
 

1. High-elastic TPU:

   Polyols containing both soft and hard segments can synthesize a better elastic TPU, exhibit soft, high-elasticity, hydrolysis-resistant and other characteristics, can be applied to retractable components such as mask ear straps.
    

2. 3D Printing TPU:

   High crystallinity glycol polyol is used to meet the demand of rapid forming. The materials show high crystallinity and excellent hand feel, which are most commonly used in 3D mask regulators.
    

3. Injection Grade TPU:

   Fast molding speed and excellent physical stability. It can be used in sealing ring, caster and gear parts with the advantages of wear resistance, grease resistance and resistance to multiple chemical substances.
    

4. Extrusion Grade TPU:

   It has balanced high and low temperature tolerance, bright and transparent, good hydrolytic resistance and anti-bacterial can be applied to medical tubing. As well as the sealing tape commonly used on fabrics, which has stable viscosity, waterproof and water pressure resistance.
    

5. Moisture-permeable Grade TPU:

   The breathable films are made of highly hygroscopic glycol polyol has high-efficiency barrier property and no micro-pores, which blocks out the bacteria and viruses while the human body's hot air is penetrating through. Mainly used in surgical gowns, protective clothing and other functional fabrics.
    

6. Melt Spinning Grade TPU:

   TPU synthesized from high purity polyester or polyether polyol, has high tensile strength, high elongation, good elasticity, soft hand touch, good light fastness and crystallinity, which is easy to process melt spinning. It can be applied to the shaping processing of various textiles.
    

7. Professional Medical TPU:

   At present, PU application in medical materials only accounts for a small part, countries are still developing new technologies and uses, and the relevant commercial promotions need to be strengthened. In recent years, CPMC has also been actively in this area to deploy and develop medical-grade TPU application of diagnostic equipment and products, to help doctors diagnose the health condition and save the lives of critically ill patients. The TPU made of polycarbonate glycol polyol with high biocompatibility isn’t easy to cause adverse reactions with human body, and can be used in surgical products such as diagnosis, anesthesia, auxiliary respiratory equipment, dental materials, wound dressings and vascular implants, or other peripheral products such as medical inflatable mattresses, medical pressure socks, medical shoes, orthotics and so on.
    

The Features of Medical grade TPU:

• Good biocompatibility

• Adapt to multiple sterilization methods

• Excellent resistance to medical device cleaners, chemicals and bacteria

• Transparent and clear, suitable for making transparent parts such as protective masks and goggles
   

Medical grade TPU requires higher quality standards:

• The polymer provided by the supplier shall be subject to the biocompatibility test on a regular basis

• Must be produced according to GMP and ISO standards

• Traceability of all raw materials and additives

• Use the least toxic additives (Lubricants, stabilizers, catalysts, etc.)

• Compliant with FDA polymer composition, manufacturing method and biocompatibility
   

B. ​Reactive Polyurethane Hot-melt Adhesive, PUR

PUR is a solvent-free, save on usage volume, weather-resistant polymer green material. Its bonding strength with the substrate is sufficient to overcome the stress and tension of the material itself, and it can solve the interface compound problem of different materials in the industrial of textile, construction and electronics. Compared with traditional adhesives, it has higher weather resistance and solvent resistance. In terms of coating process, more than one laminating methods can be selected depending on the material of finished product and end use.

Recently, with the rise of public health awareness, people have paid more attention to epidemic prevention products. In order to maximize the effectiveness of epidemic prevention, whether it is barrier gown worn by medical staff, or the bedspread such textiles used in hospitals, can be compounded by PUR which can efficiently avoid infected body fluids (blood, sweat, saliva...) infiltration.

The PUR developed by CPMC can be widely used in the bonding between cloth and cloth or cloth and film, such as medical protective textiles and medical inflatable mattresses. Due to the finished product and the human body has direct contact, it is necessary to avoid using hazardous substances that do not comply with the regulations of prohibited or restricted substances regulations in the whole supply chain, the other hand is to ensure that the end applications achieve the desired performance.
 

C. Polyurethane Adhesive for Flexible Packaging Lamination, PUA

Because of the COVID-19 outbreak, in order to prevent the spread of the epidemic, countries have implemented quarantine / isolation and even closed the city according to the situation. People who are restricted from outdoor activities start to hoard food, necessities of life and personal medicine for their own livelihood, which greatly increases the demand for packaging bags.

In order to overcome the inherent defects of single films, since 1950, the industry has focused on the development of composite flexible packaging materials; it has been gradually applied to food, medical and household products due to its good comprehensive performance. Up to now, the flexible packaging compound technology has been quite mature, and the solvent-free compound technology is more the trend of the times.

In response to the market demand, CPMC developed the following polyurethane adhesive for flexible packaging:

1. Two-component solvent-free PUA:

   It can be used to laminate general plastic structures and aluminum-plated structures, often used for portable packaging of fresh vegetables, fruits, snacks, instant noodles, etc., medium/ high-end solvent-free adhesive can even withstand high temperature retort at 121 ℃ ~ 135 ℃. It has been widely used in processing food, conditioning packages and products requiring high temperature sterilization.
    

2. Solvent-free PUA for two-component paper-plastic compound:

   Used in medical equipment, medicine, tea bags, sugar bags and powder packaging.
    

3. Customized two-component solvent-free PUA with ethyl maltol resistant:

   Barrier food additive- ethyl maltol, can be used for laminating aluminum-plastic structure, and can withstand high temperature retort at 135 ℃, suitable for special product applications.
    

Common medical and health care packaging (plastic-plastic or aluminum-plastic structure):

Package Contents	Applicable Structure	Performance Requirement
Vitamins, Supplements (ointment,  liquid)	PET//AL//PE	Antifouling, Light-shielding, Air-tightness, High Strength
Tablets, Powders, Capsules, Ointments, Infusions, etc.	OPP//PE OPP//AL//PE	Antifouling, Air-tightness