He waiwai koʻikoʻi ka paʻa wai no nā ʻoihana he nui e hoʻohana ana i nā mea hydrophilic e like me cellulose ethers. ʻO Hydroxypropylmethylcellulose (HPMC) kekahi o nā cellulose ethers me nā waiwai paʻa wai kiʻekiʻe. ʻO ka HPMC he polymer semi-synthetic i loaʻa mai ka cellulose a hoʻohana mau ʻia i nā ʻano hana like ʻole i ke kūkulu ʻana, lāʻau lapaʻau a me nā ʻoihana meaʻai.
Hoʻohana nui ʻia ʻo HPMC ma ke ʻano he mānoanoa, stabilizer a me ka emulsifier i nā huahana meaʻai like ʻole e like me ka ice cream, sauces a me nā lole e hoʻomaikaʻi ai i ko lākou ʻano, kūlike a me ke ola paʻa. Hoʻohana pū ʻia ʻo HPMC i ka hana ʻana i nā lāʻau lapaʻau i ka ʻoihana lāʻau lapaʻau ma ke ʻano he mea hoʻopaʻa, disintegrant a me ka mea hoʻopili kiʻiʻoniʻoni. Hoʻohana ʻia ʻo ia ma ke ʻano he mea mālama wai i nā mea kūkulu hale, ʻoi aku ka nui o ka sima a me ka mortar.
He waiwai koʻikoʻi ka paʻa ʻana o ka wai i ke kūkulu ʻia ʻana no ka mea kōkua ia e mālama i ka maloʻo ʻana o ka sima a me ka pahū hou. Hiki i ka maloʻo ke hoʻohaʻahaʻa a me ka haki ʻana, ka hopena i nā hale nāwaliwali a paʻa ʻole. Kōkua ʻo HPMC i ka mālama ʻana i ka wai i loko o ka sima a me ka mole ma ke komo ʻana i nā molekala wai a hoʻokuʻu mālie iā lākou i ka wā lōʻihi, e ʻae ana i nā mea kūkulu hale e hoʻōla a paʻakikī.
Hoʻokumu ʻia ke kumu mālama wai o HPMC ma kona hydrophilicity. Ma muli o ka loaʻa ʻana o nā pūʻulu hydroxyl (-OH) i loko o kāna ʻano mole, he kiʻekiʻe ka HPMC i ka wai. Hoʻopili nā pūʻulu hydroxyl me nā molekele wai e hana i nā paʻa hydrogen, ka hopena i ke kūkulu ʻia ʻana o kahi pūpū hydration a puni nā kaulahao polymer. Hiki i ka pūpū hydrated ke hoʻonui i nā kaulahao polymer, e hoʻonui ana i ka nui o HPMC.
ʻO ka pehu ʻana o HPMC he kaʻina hana ikaika e hilinaʻi ʻia ma nā ʻano like ʻole e like me ke degere o ka hoʻololi ʻana (DS), ka nui o ka ʻāpana, ka mahana a me ka pH. ʻO ka degere o ka hoʻololi ʻana e pili ana i ka helu o nā pūʻulu hydroxyl i hoʻololi ʻia i kēlā me kēia ʻāpana anhydroglucose i ke kaulahao cellulose. ʻO ke kiʻekiʻe o ka waiwai DS, ʻoi aku ka kiʻekiʻe o ka hydrophilicity a ʻoi aku ka maikaʻi o ka hana paʻa wai. Hoʻopili pū ka nui o ka HPMC i ka paʻa ʻana o ka wai, no ka mea, ʻoi aku ka nui o ka ʻili o nā ʻāpana liʻiliʻi i kēlā me kēia ʻāpana nui, a ʻoi aku ka nui o ka komo ʻana o ka wai. Hoʻopili ka wela a me ka waiwai pH i ke kiʻekiʻe o ka pehu a me ka paʻa ʻana o ka wai, a ʻo ke kiʻekiʻe o ka mahana a me ka waiwai pH haʻahaʻa e hoʻonui ai i ka pehu a me nā waiwai paʻa wai o HPMC.
ʻO ka mīkini paʻa wai o HPMC e pili ana i ʻelua kaʻina: absorption a desorption. I ka wā o ka absorption, hoʻopili ʻo HPMC i nā molekala wai mai ke kaiapuni a puni, e hana ana i ka pūpū hydration a puni nā kaulahao polymer. Mālama ka pūpū wai i ka hāʻule ʻana o nā kaulahao polymer a hoʻokaʻawale iā lākou, e alakaʻi ana i ka pehu o ka HPMC. Hoʻokumu nā molekele wai i hoʻopaʻa ʻia me nā pūʻulu hydroxyl i HPMC, e hoʻonui ana i ka hana mālama wai.
I ka wā desorption, hoʻokuʻu mālie ʻo HPMC i nā molekala wai, e ʻae i ka mea hale e hoʻōla pono. ʻO ka hoʻokuʻu lohi ʻana o nā molekole wai e hōʻoia i ka hoʻomaʻemaʻe piha ʻana o ka sima a me ka mortar, ka hopena i kahi hale paʻa a paʻa. ʻO ka hoʻokuʻu lohi ʻana o nā molekala wai e hāʻawi pū i ka wai mau i ka sima a me ka mortar, e hoʻonui ai i ke kaʻina hana hoʻōla a hoʻonui i ka ikaika a me ka paʻa o ka huahana hope.
I ka hōʻuluʻulu ʻana, he waiwai koʻikoʻi ka mālama ʻana i ka wai no nā ʻoihana he nui e hoʻohana ana i nā mea hydrophilic e like me cellulose ethers. ʻO HPMC kekahi o nā cellulose ethers me nā waiwai paʻa wai kiʻekiʻe a hoʻohana nui ʻia i ke kūkulu hale, lāʻau lapaʻau a me nā ʻoihana meaʻai. Hoʻokumu ʻia ka waiwai paʻa wai o HPMC i kona hydrophilicity, kahi e hiki ai iā ia ke hoʻomoʻa i nā molekala wai mai ka ʻāina a puni, e hana ana i ka pūpū hydration a puni nā kaulahao polymer. ʻO ka pūpū hydrated ka mea e pehu ai ka HPMC, a ʻo ka hoʻokuʻu lohi ʻana o nā molekala wai e hōʻoiaʻiʻo i ka hoʻomaʻemaʻe piha ʻana o nā mea hale, ka hopena i kahi hale paʻa a paʻa.
Ka manawa hoʻouna: ʻAukake-24-2023