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A waterproof tablecloth is an indispensable accessory for anyone seeking to combine functionality wi...
waterproof tablecloth
2025-08-16 09:20
Navigating the vast world of utility carts can be daunting, but for those searching for a reliable,...
4 wheel utility cart with liner
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The Essential Guide to Choosing an 8kg Washing Machine Cover As we navigate our busy lives, our appl...
8kg washing machine cover
2025-08-16 09:00
Găng tay tạo kiểu chống nhiệt Giải pháp hoàn hảo cho tóc Trong thế giới làm đẹp, việc tạo kiểu tóc k...
Găng tay chịu nhiệt
2025-08-16 08:57
ማስታወቂያ የእርቅ አወቃቀር መከለያ ይሁን የእንጽ የማስታወቂያን ዕውቀት በኣዳም የተደገመ ሐሳብ ወይም የሚታወቅ የመነሻ ምንጭ ነው። ከሚናገር ሁሉ ለእንጽ ይህ...
ትቢያ መክፈቻ ለመቀላቀል
2025-08-16 08:36
The Elegance of White Oval Tablecloths A Perfect Addition to Your Dining Experience When it comes to...
white oval tablecloth
2025-08-16 08:28
Choosing the right canvas ironing board cover is crucial for achieving wrinkle-free clothes while en...
canvas ironing board cover
2025-08-16 08:17
For those who seek efficiency in maintaining a polished wardrobe, owning the right accessories can m...
extra long and wide ironing board cover
2025-08-16 07:53
Finding the perfect ironing board cover might not be at the top of everyone's to-do list, but for th...
ironing board cover with measurements
2025-08-16 07:38
Gone are the days of using dreary, uninspiring ironing board covers that make an already mundane cho...
funny iron board covers
2025-08-16 07:36
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  • Latest articles
    1: What is HPMC?
    Hydroxypropyl methylcellulose ( (Propylene glycol ether of methylcellulose) is a methylcellulose modified with a small amount of propylene glycol ether groups attached to the anhydroglucose of the cellulose. The dry product contains 19 to 30 per cent of methoxyl (-OCH3) groups and 3 to 12 per cent of hydroxypropyl (-OCH2CHOHCH3) groups. HPMC can be derived from tree fiber or cotton fiber.

    2: How HPMC is made:
    The cellulose ethers are manufactured by a reaction of purified cellulose with alkylating reagents (methyl chloride) in presence of a base, typically
    sodium hydroxide and an inert diluent. The addition of the base in combination with water activates the cellulose matrix by disrupting the crystalline structure and increasing the access for the alkylating agent and promotes the etherification reaction. This activated matrix is called alkali cellulose (Kirk-Othmer, 1993). During the manufacture of HPMC alkali cellulose reacts with methyl chloride to produce methyl cellulose and sodium chloride. Side reactions of the methyl chloride and sodium hydroxide produce methanol and dimethyl ether by-products. The methylcellulose is then further reacted with the staged addition of an alkylene oxide, which in the case of HPMC is propylene oxide (Kirk Othmer, 1993 Dow, 2002). After this reaction, MC and HPMC are purified in hot water, where they are insoluble. Drying and grinding completes the process.

    3: Chemicals agents and reactions:
    The chemical reactions of manufacturing HPMC summerize as following: