Since the properties of hydroxypropyl methylcellulose are similar to other water-soluble ethers, it can be used in emulsion coatings and water-soluble resin coating components as a film-forming agent, thickener, emulsifier and stabilizer, etc., which gives the coating film good abrasion resistance. Homogeneous coating and adhesion, and improved surface tension, stability to acids and bases, and compatibility with metal pigments.
Since HPMC has a higher gel point than MC, it is also more resistant to bacterial attack than other cellulose ethers, and thus can be used as a thickening agent for aqueous emulsion coatings. HPMC has good viscosity storage stability and its excellent dispersibility, thus HPMC is particularly suitable as a dispersant in emulsion coatings.
The application of hydroxypropyl methyl cellulose in the coating industry is as follows.
1.various viscosity HPMC configuration paint wear resistance, high temperature resistance, anti-bacterial explanation, washing resistance and stability to acids and bases are better; it can also be used as a paint stripper containing methanol, ethanol, propanol, isopropyl alcohol, ethylene glycol, acetone, methyl ethyl ketone or diketone alcohol thickener; HPMC formulated emulsified coatings have excellent wet abrasion; HPMC than HEC and EHEC and CMC as HPMC has better effect than HEC and EHEC and CMC as paint thickener.
2.Highly substituted hydroxypropyl methyl cellulose has better resistance to bacterial attack than low substitution, and has better viscosity stability in polyvinyl acetate thickeners. Other cellulose ethers are in storage due to the chain degradation of cellulose ether and make the coating viscosity reduced.
3.paint stripper can be water-soluble HPMC (where methoxy is 28% to 32%, hydroxypropoxy is 7% to 12%), dioxymethane, toluene, paraffin, ethanol, methanol configuration, it will be applied to the upright surface, with the required viscosity and volatility. This paint stripper removes most conventional spray paints, varnishes, enamels, and certain epoxy esters, epoxy amides, catalyzed epoxy amides, acrylates, etc. Many paints can be peeled off in a few seconds, some paints need 10~15min or more, this paint stripper is especially suitable for wood surfaces.
4.Water emulsion paint can be composed of 100 parts of inorganic or organic pigment, 0.5~20 parts of water-soluble alkyl cellulose or hydroxyalkyl cellulose and 0.01~5 parts of polyoxyethylene ether or ether ester. For example, the colorant is obtained by mixing 1.5 parts of HPMC, 0.05 parts of polyethylene glycol alkyl phenyl ether, 99.7 parts of titanium dioxide and 0.3 parts of carbon black. The mixture is then stirred with 100 parts of 50% solid polyvinyl acetate to obtain the coating, and there is no difference between the dry coating film formed by applying it on thick paper and rubbing it lightly with a brush.
Post time: May-20-2022