Views: 267 Author: Vickey Publish Time: 2023-08-14 Origin: Site
As a short form of hydroxypropyl methylcellulose (HPMC), hypromellose (INN), also known as hydroxypropyl methylcellulose, is a semi-synthetic, inert, viscoelastic polymer utilized in eye drops as well as an excipient and controlled-delivery component in oral medications. As a food ingredient, hypromellose functions as a thickening, suspending, and emulsifying agent as well as a substitute for animal gelatin. Its E464 Codex Alimentarius code identifies it.
Hypromellose is a solid that has an appearance ranging from slightly off-white to beige powder and may be made into granules. When the substance is dissolved in water, colloids are created. This non-toxic component can react violently with oxidizing chemicals and is flammable.
Hypromellose Pour certain solvents, such as a suitable ratio of ethanol to water, propanol to water, etc., into water and dissolve. The aqueous solution is active at the surface.High transparency, stable performance, different gel temperatures, solubility that changes with viscosity (the more solubility, the lower the viscosity), performance differences between different HPMC specifications, and pH value have no bearing on HPMC's solubility in water.
Methoxy concentration, gel point, water solubility, and surface activity all led to a drop in HPMC. Additionally, HPMC has good film formation, salt resistance, low ash powder, pH stability, water retention, dimensional stability, wide enzyme resistance, and outstanding dispersion and bonding properties.
To ensure that the average polymerization of alkali fiber was within the acceptable range, the refined cotton cellulose was treated with alkali liquor at 35–40°C for 30 minutes, pressed, and the cellulose was crushed and correctly aged at 35°C. Propylene oxide and chlorochloride were progressively added to the alkali fiber in the etherification kettle for etherification at 50–80 °C for 5 hours with a maximum pressure of around 1.8 MPa.
Then, to increase the volume, add the required amount of hydrochloric acid and oxalic acid washing material to 90°C of hot water. Using a centrifuge, dehydrate, then wash until neutral.If the water content in the material is less than 60%, dry to a hot air flow below 5%, and finally crush the finished product through 20 mesh.
Hypromellose As a thickener, dispersant, adhesive, excipient, oil-resistant coating, filler, emulsifier, and stabilizer in the textile sector. Hypromellose In addition, it finds extensive usage in the synthetic resin, petrochemical, ceramic, paper, leather, pharmaceutical, food, and cosmetics sectors.
Hypromellose works as a water retainer and cement mortar retardant to make the mortar pump. Improve the daub and increase the operational time when used as an adhesive in plaster, gypsum material, putty powder, or other building materials. Reduce cement dosage when used as paste in ceramic tile, marble, plastic decorations, and paste enhancer. The HPMC's ability to retain water prevents the slurry from cracking as a result of drying too quickly after daub, increasing its strength after hardening.
It may be dissolved in cold water to create a specific viscous solution, and because it has qualities similar to the viscoelastic components of tears (mostly mucin), such as hydroxypromethcellulose, it can be used as a substitute for tears. In order to enhance the state of ocular mucin reduction and lengthen the retention period of the eye in the state of tear reduction, the mechanism of action involves the adsorption of polymer onto the surface of the eyeball.
This mimics the impact of conjunctival mucin. Since this adsorption is not dependent on the solution's viscosity, the lower-viscosity solution can have a long-lasting wetting effect.In addition, increase the wetting effect of the cornea by reducing the contact angle of the clean corneal surface.
