A Detailed Explanation of Polymers in Medical Isolation Goggles

Medical isolation goggles are eye protection equipment used in medical institutions to protect the eyes during examinations and treatments, preventing fluids or blood from splashing into the eyes. For the many medical staff who have direct contact with patients, medical isolation goggles, protective screens, etc., have become essential protective equipment to ensure their health. So, what material are medical isolation goggles made of? What are their performance characteristics?

Medical Isolation Goggles: Playing a Crucial Protective Role

Medical isolation goggles, also known as protective goggles, are a type of eye protection equipment among security products. According to different environmental needs, they can prevent liquid splashes, harmful light (such as strong visible light, infrared, ultraviolet, laser, etc.), high-speed particle impacts, dust, and other effects. Medical isolation goggles are generally composed of lenses, frames, and straps.

Generally speaking, medical isolation goggles need to have corrosion resistance to prevent some strongly corrosive medicines from causing damage; impact resistance to prevent objects that could harm the eyes during close-up surgery; good anti-fog performance to ensure clear vision for medical personnel.

During the diagnosis and treatment, and nursing procedures of medical staff, situations such as splashing of patient blood, body fluids, secretions, etc.; close contact with patients with droplet-transmitted infectious diseases; close-distance operations such as tracheotomy and tracheal intubation on respiratory infection patients which might lead to splashing of body fluids, blood, or secretions, medical isolation goggles play an important protective role. This is crucial for protecting the health of medical personnel who are fighting on the front lines against epidemics.

Materials of Medical Isolation Goggles

Thermoplastic Lens: Polymethyl Methacrylate

PMMA is a high molecular compound obtained by the polymerization of acrylic acid and its esters, with advantages like high transparency, low cost, easy mechanical processing, making it a widely used glass substitute material. The spectral transmittance of this material is not less than 90%, the color rendering index is not less than 90, the ultraviolet radiation filter rate is not less than 99%, the ultraviolet harm reduction rate is not less than 99%, and the retinal blue light damage reduction rate is not less than 25%. PMMA has 10 times the impact resistance strength of ordinary glass, and a light transmittance that can generally reach 92%~93%. Protective goggles made with acrylic lenses have the benefits of being lightweight but strong, easy to process, and offering a wide field of view.

Thermoset Lens: Polycarbonate

Polycarbonate (PC) is currently the most widely used material for medical isolation goggle lenses, a polymer containing carbonate groups in its molecular chain. Depending on the structure of the ester groups, it can be divided into several types such as aliphatic, aromatic, and aliphatic-aromatic. PC's chemical and physical properties are more stable than other light-transmitting materials, lighter and thinner than traditional glass lenses, and have unique characteristics such as high light transmittance, high refractive index, high impact resistance, dimensional stability, and easy processing and molding.

Anti-Fog Coating: Polymeric Materials

Besides selecting lens materials based on application environment and specific needs, various anti-fog and anti-scratch coatings need to be added to the lenses to improve the user-friendliness of medical isolation goggles.

Medical isolation goggles require high sealing performance, which brings the problem of lenses fogging up. If medical staff frequently remove their goggles to clear the fog, it would expose their eyes to potentially dangerous working environments, leading to possible impacts and hazards from foreign objects.

Additional Protection: Hydrocolloid Dressing

Usually, wearing medical isolation goggles should not exceed 2 hours, and every 30-50 minutes, they should be slightly adjusted or removed for a 10-minute break. However, medical personnel on the frontline against new coronavirus often have very intense workloads and frequently need to wear them for 3-5 hours or even longer, causing pressure injuries on the forehead, nose, cheekbones, and behind the ears.

For such situations, experts recommend the following protection methods. Make medical hydrocolloid dressings with a waterproof backing, a hydrocolloid matrix, and a covering film, and cut them to a width more than twice the pressing edge of the medical isolation goggles for the forehead, nose, left and right cheekbones, and behind the ears. Then, apply the cut hydrocolloid dressing to the corresponding parts of the face, and correctly wear the mask and medical isolation goggles as per standard requirements.

Hydrocolloid dressings do not cause allergies or harm due to zinc oxide content like band-aids or tapes, and do not stick to the skin, ensuring good sealing after wearing medical isolation goggles. Additionally, as functional dressings, they promote the healing of small pre-existing facial wounds.