Hākawa: āhuatanga whānui, me te tono

Hākawa o - hua whakauru o ngā ngota hauwai o nga rōpū hydroxyl o ngā waikawa me te waikawa kohuke i waro tuwhena. Te wehe ki Pālesi, di- me ngā pūhui. tīari reo, waikawa di- me polybasic, waikawa monobasic ki - tonu me te waikawa hākawa. Kei hākawa Taitara o te ingoa, wāhi i roto i tona hanganga o te waikawa me te waipiro. No te hākawa, whakamahia pinepine nomenclature konei mama o mua ranei. E ai ki ngā ingoa nomenclature IUPAC efirov i hanga e whai ake: tangohia he waipiro taitara tuwhena i tapiritia rite te ingoa waikawa pūwaro, me te mutu -oat. Hei tauira, kei te ingoa nga tātai hanganga o ngā hākawa (me poinanaha metamers) e ōrite ana ki te tātai rāpoi S4N802, i nomenclatures rerekē: propilformiat (propilmetanoat) izopropilformiat (izopripilmetanoat), Ethyl tāpia (etiletanoat) melpropionat (methylpropanoate).

Te whakarite o hākawa. E whānui tohaina ēnei pūhui i roto i te natura. Ko te kupu, ngā hākawa o iti taimaha rāpoi, me te reo ngā waikawa raupapa huirua he wahi o hinu faufaa o otaota maha (hei tauira, hākawa uksusnoizoamilovy ranei "ngako pea", i te mea wahi o te terise, me te maha ngā tae), me ngā hākawa o te nonireka me teitei waikawa ngakongako - pūtake matū o te ngako katoa me hinu. Kua rite ētahi hākawa synthetically.

Ko te tauhohenga hākawatanga e wahi i te pāhekoheko o waikawa (me te kohuke) waikawa ki waiwaihā. mahi te whakakōkī rite he (H2S04 tino whakamahia nuitia) waikawa kohuke kaha. Ko te rāpoi ngota whakakōkī whakahohetia te waikawa.

Ko te tere o te tauhohenga o tei hoki hākawatanga i runga i te rōpū OH hāngai ana (tuatahi, tuarua ranei tuatoru) ki tetahi ngota waro i runga i te āhua matū o te waikawa me te waipiro, me te hanganga waiwaro mekameka, e pā nei te ki te carboxyl.

Tauhohenga wai o nga hākawa. Ko te tauhohenga paparetanga (saponification) hākawa - ko te tauhohenga anga whakamuri o hākawatanga. haere te reira i āta. Ki te tapiritia ki te ranunga tauhohe, te ranunga o ngā waikawa kohuke kawakore ranei, ona piki tere. e saponification alkali tuu i te mano nga wa tere atu i te waikawa. E hydrolyzed te hākawa i roto i te reo kawakore, me ethers - i roto i te waikawa.

Ki runga ki ngā hākawa whakawera ki waiwaihā i te aroaro o te ngāwhā waikawa alcoholates (reo kawakore) puta alkoxy utu ranei. hanga tenei te hākawa hou, a ka hoki te reo tauhohenga te waipiro, i mua i roto i te puka o ngā toenga i roto i te rāpoi ngota hākawa.

Hākawa whakaiti tauhohenga. He tino maha whakaiti āpiha hydride konumohe lithium, te konutai i roto i te waipiro kohua. Hākawa o ātete tiketike ki te mahi o ngā hāora e whakamahia ana i roto i te kōtuitanga matū tātari ranei ki te te tiaki i ngā rōpū kava, me te phenolic.

Hākawa māngai matua. whiwhi ehākawa Ethyl (Etera ahetiki) e te tauhohenga hākawatanga o te waihā me te whakakōkī waikawa tāpia ( ngāwhā waikawa). whakamahia Ethyl ehākawa te rite te whakarewa o te cellulose pākawa i te hanga o te auahi paura, me te kiriata whakaahua, hua essences wāhanga mo te ahumahi kai.

Izoamiletanoat (Etera uksusnoizoamilovy, "ngako pea") he tino wairewa i ewaro, diethyl Etere. i rite tāpia i hākawatanga o waikawa me te isoamyl waipiro. whakamahia Izoamilmetilbutanoat rite te wähanga hā i roto i te mea kakara, me te rite te whakarewa.

Izoamilizovaleriat ( "aporo" uho, Etera izovalerianovoizoamilovy) whiwhi e te tauhohe i te hākawatanga waikawa isovaleric me waipiro isoamyl. whakamahia hākawa mea te rite te essences hua i roto i te ahumahi kai.