01. Te whakaurunga o te cellulose
Ko te cellulose he polysaccharide macromolecular i hangaia mai i te glucose. Kāore e rewa i roto i te wai me ngā whakarewa rauropi whānui. Koinei te wāhanga matua o te pakitara pūtau tipu, ā, koia hoki te polysaccharide tino horapa me te tino nui i roto i te taiao.
Ko te cellulose te rauemi whakahou nui rawa atu o te ao, ā, koia anō hoki te pūmua taiao e nui rawa ana te kohikohinga. He painga ōna, he whakahou, he pirau katoa, ā, he pai te hototahi ki te koiora.
02. Ngā take mō te whakarerekē i te cellulose
He nui ngā rōpū -OH kei roto i ngā macromolecules cellulose. Nā te pānga o ngā here hauwai, he nui te kaha i waenga i ngā macromolecules, ka hua ake he enthalpy rewa nui △H; i tētahi atu ringa, he mowhiti kei roto i ngā macromolecules cellulose. Pērā i te hanganga, he nui ake te pakari o te mekameka ngota, ka hua ake he iti ake te huringa entropy rewa ΔS. Nā ēnei take e rua ka piki ake te pāmahana o te cellulose rewa (= △H / △S), ā, ka iti iho te pāmahana pirau o te cellulose. Nō reira, ina werahia te cellulose ki tētahi pāmahana, ka puta te āhuatanga kua pirau te cellulose i mua i te tīmatanga o te rewa, nō reira, kāore e taea e te tukatuka rauemi cellulose te tango i te tikanga o te rewa tuatahi, kātahi ka whakahāngai.
03. Te hiranga o te whakarerekētanga o te cellulose
I te mimiti haere o ngā rauemi pūngāwerewere me te piki haere o ngā raruraru taiao e hua mai ana i ngā para o ngā muka matū o ngā kakahu, kua noho te whanaketanga me te whakamahinga o ngā rauemi muka taiao hou hei tetahi o ngā wāhi wera e arohia ana e te tangata. Ko te Cellulose te rauemi taiao hou rawa atu i roto i te taiao. He āhuatanga pai rawa atu ōna pēnei i te pai o te waiora, te ārai i te mate, te kaha o te uruhanga o te hau, te pai o te tae, te whakamarie ki te mau, te ngāwari ki te tukatuka kakahu, me te pirau koiora. He āhuatanga kāore e taea te whakataurite ki ngā muka matū.
He nui ngā rōpū hydroxyl kei roto i ngā ngota cellulose, he ngāwari ki te hanga hononga hauwai ā-roto me ā-waenga, ā, ka memeha i ngā pāmahana teitei me te kore e rewa. Heoi, he pai te tauhohenga o te cellulose, ā, ka taea te whakangaro i tōna hononga hauwai mā te whakarerekētanga matū, mā te tauhohenga honohono rānei, ka taea ai te whakaiti i te ira rewa. Hei momo hua ahumahi, he whānuitia te whakamahinga i roto i ngā kakahu, te wehenga kiriuhi, te kirihou, te tupeka me ngā paninga.
04. Te whakarerekētanga o te whakaetere o te cellulose
Ko te cellulose ether he momo hua cellulose i whiwhihia mā te whakaetherification o te cellulose. He whānuitia te whakamahinga nā te mea he pai rawa atu ki te whakamātotoru, ki te emulsification, ki te whakatārewatanga, ki te hanga kiriata, ki te colloid tiaki, ki te pupuri makuku, me te piri. E whakamahia ana i roto i te kai, te rongoā, te hanga pepa, te peita, ngā rauemi hanga, me ētahi atu.
Ko te whakapūmautanga o te cellulose he raupapa o ngā hua i puta mai i te tauhohenga o ngā rōpū hydroxyl i runga i te mekameka ngota cellulose me ngā kaihoko alkylating i raro i ngā āhuatanga kawakore. Mā te kai i ngā rōpū hydroxyl ka whakaitihia te maha o ngā here hauwai i waenga i ngā ngota hei whakaiti i ngā kaha i waenga i ngā ngota, ā, ka whakapai ake i te pumau wera o te cellulose, ka whakapai ake i te mahi tukatuka o ngā rauemi, ā, i te wa ano ka whakaitihia te ira rewa o te cellulose.
Ngā tauira o ngā pānga o te whakarerekētanga etherification ki ētahi atu mahi a te cellulose:
Mā te whakamahi i te miro kua whakapaia hei rauemi mata taketake, i whakamahia e ngā kairangahau tētahi tukanga whakapūmau kotahi-taahiraa hei whakarite i te matatini etera carboxymethyl hydroxypropyl cellulose me te tauhohenga ōrite, te matotoru teitei, te ātete waikawa pai me te ātete tote mā te tauhohenga alkaliization me te whakapūmau. Mā te whakamahi i te tukanga whakapūmau kotahi-taahiraa, he pai te ātete tote, te ātete waikawa me te wairewa o te carboxymethyl hydroxypropyl cellulose kua whakaputaina. Mā te whakarerekē i te nui o te propylene oxide me te waikawa chloroacetic, ka taea te whakarite i ngā hua he rerekē te ihirangi carboxymethyl me te hydroxypropyl. E whakaatu ana ngā hua whakamātautau he poto te huringa whakaputa o te carboxymethyl hydroxypropyl cellulose i whakaputaina mā te tikanga kotahi-taahiraa, he iti te whakamahinga whakarewa, ā, he tino pai te ātete o te hua ki ngā tote monovalent me te divalent me te ātete waikawa pai.
05. Te tirohanga mō te whakarerekētanga o te cellulose etherification
He matū nui te cellulose, he rauemi mata matū hoki, he nui ngā rauemi, he matomato, he pai hoki mō te taiao, ā, he mea whakahou anō hoki. He tino pai te mahi a ngā hua o te whakarerekētanga cellulose etherification, he whānui ngā whakamahinga me ngā pānga whakamahinga pai rawa atu, ā, he nui te whakatutuki i ngā hiahia o te ōhanga ā-motu. Ā, ko ngā hiahia o te whanaketanga pāpori, me te haere tonu o te ahunga whakamua hangarau me te whakatutukitanga o te hokohoko ā muri ake nei, ki te taea te whakawhānui ake i te ahumahi o ngā rauemi mata hangai me ngā tikanga hangai o ngā hua cellulose, ka nui ake te whakamahinga me te whakatutuki i te whānuitanga o ngā tono. Uara
Te wā tuku: 20-Pepuere-2023