Rosin cob
Nyob rau tib lub sijhawm, nws kuj muaj cov tshuaj tiv thaiv carboxyl xws li esterification, alcoholization, ntsev tsim, decarboxylation, thiab aminolysis.
Qhov thib ob reprocessing ntawm rosin yog raws li tus yam ntxwv ntawm rosin nrog ob daim ntawv cog lus thiab carboxyl pawg, thiab cov rosin yog hloov los tsim ib tug series ntawm hloov rosin, uas txhim kho kev siv tus nqi ntawm rosin.
Rosin resin yog siv rau hauv kev lag luam nplaum kom nce viscosity, hloov cov nplaum nplaum, cohesive zog, thiab lwm yam.
Rosin resin yog tricyclic diterpenoid compound, tau nyob rau hauv monoclinic flaky crystals hauv aqueous ethanol. Lub melting point yog 172 ~ 175 ° C, thiab qhov kho qhov muag rotation yog 102 ° (anhydrous ethanol). Insoluble hauv dej, soluble hauv ethanol, benzene, chloroform, ether, acetone, carbon disulfide thiab dilute aqueous sodium hydroxide tov.
Nws yog cov khoom tseem ceeb ntawm ntuj rosin resin. Esters ntawm rosin acids (xws li methyl esters, vinyl cawv esters, thiab glycerides) yog siv nyob rau hauv cov xim thiab varnishes, tab sis kuj nyob rau hauv xab npum, yas, thiab resins.
Nws yog polyol ester ntawm rosin acid. Feem ntau siv polyols yog glycerol thiab pentaerythritol. Cov polyol
Lub softening point ntawm pentaerythritol rosin ester yog siab dua li ntawm glycerol rosin ester, thiab kev ua kom qhuav, hardness, dej tsis kam thiab lwm yam khoom ntawm cov kua roj vanish yog zoo dua li cov kua roj vanish ua los ntawm glycerol rosin ester.
Yog tias cov ester sib raug zoo ua los ntawm polymerized rosin los yog hydrogenated rosin yog siv los ua cov khoom siv raw, qhov kev nyiam ntawm kev hloov xim yog txo, thiab lwm yam khoom kuj tau txhim kho rau qee yam. Lub softening point ntawm polymerized rosin ester yog siab dua li ntawm rosin ester, thaum lub softening point ntawm hydrogenated rosin ester yog qis dua.
Rosin esters yog refined los ntawm rosin resins. Rosin resin yog tsim los ntawm esterification ntawm rosin. Piv txwv li, rosin glyceride yog ua los ntawm rosin los ntawm esterification ntawm glycerol.
Lub ntsiab tivthaiv ntawm rosin resin yog resin acid, uas yog sib tov ntawm isomers nrog cov mis mos molecular C19H29 COOH; rosin ester yog hais txog cov khoom tau txais tom qab esterification ntawm rosin resin, vim nws yog ib yam khoom sib txawv, yog li nws tsis tuaj yeem hais tias nws yog qhov twg. loj.
Rosin-hloov phenolic resin tseem yog qhov tseem ceeb ntawm cov txheej txheem kev sib xyaw ua ke. Cov txheej txheem ib-kauj ruam yog sib tov phenol, aldehyde thiab lwm yam khoom siv raw nrog rosin thiab tom qab ntawd cuam tshuam ncaj qha.
Daim ntawv txheej txheem yog qhov yooj yim, tab sis cov kev tswj xyuas xws li cov cua sov tom ntej yog qhov siab; cov txheej txheem ob-kauj ruam yog los tsim cov phenolic condensate nruab nrab ua ntej, thiab tom qab ntawd hnov mob nrog rosin system.
Txhua qhov tshwj xeeb cov tshuaj tiv thaiv thaum kawg tsim cov resin nrog tus nqi qis, qhov muag muag siab, thiab qhov sib piv molecular hnyav thiab qee qhov solubility hauv cov roj ntxhia cov kuab tshuaj.
1. Ib-kauj ruam txheej txheem Reaction txoj cai:
Synthesis of resole phenolic resin: Alkylphenol yog ntxiv rau molten rosin, thiab paraformaldehyde muaj nyob rau hauv lub cev hauv daim ntawv granular, thiab tom qab ntawd decomposes rau hauv monomer formaldehyde, uas dhau los ua cov tshuaj tiv thaiv polycondensation nrog alkylphenol.
Kev tsim ntawm methine quinone: lub cev qhuav dej ntawm qhov kub siab, hauv cov txheej txheem cua sov, kev ua haujlwm ntawm methylol hauv lub cev nce nrawm, lub cev qhuav dej hauv methylol molecule tshwm sim, thiab cov condensation etherification cov tshuaj tiv thaiv ntawm methylol molecules tshwm sim, tsim. Muaj ntau hom phenolic condensates nrog ntau qib ntawm polymerization muaj.
Ntxiv ntawm rosin rau methine quinone thiab maleic anhydride: Ntxiv cov txiv neej anhydride ntawm 180 ° C, siv cov unsaturated ob daim ntawv cog lus ntawm maleic anhydride thiab ob daim ntawv cog lus hauv rosin acid ntxiv, thiab ib txhij ntxiv methine quinone rau rosin. Cov kua qaub kuj dhau los ua Diels-Alder ntxiv cov tshuaj tiv thaiv los tsim cov txiv neej anhydride chromofuran tebchaw.
â, £ Esterification ntawm polyol: Lub hav zoov ntawm ntau pawg carboxyl nyob rau hauv lub kaw lus yuav rhuav tshem qhov sib npaug ntawm cov kab ke thiab ua rau cov resin tsis ruaj khov.
Yog li ntawd, peb ntxiv polyols thiab siv cov esterification cov tshuaj tiv thaiv ntawm hydroxyl pawg ntawm polyols thiab carboxyl pawg nyob rau hauv lub system los txo cov acid nqi ntawm lub system. Nyob rau tib lub sijhawm, los ntawm esterification ntawm polyols, siab polymers haum rau offset printing inks yog tsim.
2. Ob-kauj ruam txheej txheem Reaction txoj cai:
Nyob rau hauv qhov kev txiav txim ntawm ib tug tshwj xeeb catalyst, formaldehyde tsim ib tug ntau yam ntawm resole phenolic oligomers uas muaj ib tug loj npaum li cas ntawm active methylol nyob rau hauv cov tshuaj ntawm alkylphenol. Txij li thaum lub kaw lus tsis muaj cov nyhuv inhibitory ntawm rosin acid, condensates nrog ntau tshaj 5 phenolic structural units tuaj yeem ua ke.
Polyol thiab rosin yog esterified ntawm qhov kub thiab txias, thiab nyob rau hauv qhov kev txiav txim ntawm cov catalyst yooj yim, cov kua qaub yuav tsum tau mus txog sai.
⢠Nyob rau hauv rosin polyol ester uas tau hnov mob, maj mam ntxiv cov synthesized resole phenolic resin dropwise, tswj lub dropwise ntxiv tus nqi thiab kub, thiab ua kom tiav cov dropwise ntxiv. Lub cev qhuav dej ntawm qhov kub thiab txias, thiab thaum kawg qhov xav tau resin yog tsim.
Qhov kom zoo dua ntawm cov txheej txheem ib-kauj ruam yog cov pov tseg raug tshem tawm hauv daim ntawv ntawm chav dej, uas yog ib qho yooj yim rau kev tiv thaiv ib puag ncig. Txawm li cas los xij, phenolic condensation cov tshuaj tiv thaiv uas tshwm sim nyob rau hauv molten rosin yog feem ntau tshwm sim los ntawm cov tshuaj tiv thaiv kub thiab tsis sib xws.
Kev hloov kho yog qhov nyuaj rau kev tswj hwm, thiab nws tsis yooj yim kom tau txais cov khoom lag luam ruaj khov. Qhov kom zoo dua ntawm txoj kev ob kauj ruam yog tias phenolic condensation oligomer nrog cov qauv ruaj khov thiab muaj pes tsawg leeg tuaj yeem tau txais, txhua theem tshuaj tiv thaiv yog yooj yim los saib xyuas, thiab cov khoom zoo kuj tseem ruaj khov.
Qhov tsis zoo yog tias cov tsoos phenolic pulp condensate yuav tsum tau nruab nrab los ntawm cov kua qaub thiab yaug nrog dej ntau kom tshem tawm ntsev ua ntej nws tuaj yeem cuam tshuam nrog cov rosin, ua rau muaj ntau cov phenol-muaj cov dej khib nyiab, uas ua rau muaj kev puas tsuaj loj. ib puag ncig thiab siv sijhawm ntau.
Cov lus nug ntawm txoj cai thiab tsis ncaj ncees ntawm cov txheej txheem ib-kauj ruam thiab ob-kauj ruam tau ntev tau ua kom pom tseeb ntawm cov tuam txhab number case. Tab sis tsis ntev los no, nrog rau txoj kev vam meej ntawm txoj kev tsis ntxuav rau synthesizing phenolic condensate, rationalization ntawm ob-kauj ruam synthesis txoj kev tau txhawb zog.
