Ii-sealants ze-silicone ziye zaba lukhetho lokuqala lweengcali kunye nabantu abazisebenzisayo xa kufikwa ekutywineni iindawo ezahlukeneyo. Ii-sealants ze-silicone zineempawu zokuncamathelisa ezibalaseleyo kunye nokuguquguquka, zibonelela ngokuqina okuhle kakhulu ixesha elide kwiindlela ezahlukeneyo zokusetyenziswa. Phakathi kweentlobo zee-sealants ze-silicone ezithengiswa kwimarike, ii-sealants ze-alkoxy silicone kunye nee-sealants ze-acetoxy silicone zezona ntlobo zimbini zidumileyo. Kule ndaba, siza kujonga ngokunzulu iimpawu zezi sealants, izinto ezilungileyo kunye neengxaki zazo, kwaye sikuncede umisele ukhetho olufanelekileyo kwiimfuno zakho ezithile.
1. Umahluko kwisakhiwo:
Okokuqala, makhe sihlolisise umahluko wolwakhiwo phakathi kwe-alkoxy kunye ne-acetoxy. Iqela le-alkoxy liqulathe iqela le-alkyl (R-) elidityaniswe ne-atom yeoksijini (-O-). Ngokuyintloko, ludibaniso lweqela le-alkyl kunye neoksijini.
Kwelinye icala, i-acetoxy ifumaneka kwi-acetic acid. Iquka iqela le-acetyl (CH3CO-) elidityaniswe ne-atom yeoksijini (-O-). Ngoko ke, i-acetoxy ingathathwa njengeqela le-alkyl elithathelwe indawo yioksijini ngaphakathi kwe-acetyl moiety.
Umahluko kwisakhiwo ukhokelela kumahluko kwiipropati zeekhemikhali kunye nokusebenza kwakhona phakathi kwamaqela e-alkoxy kunye ne-acetoxy. Njengeqela elisebenzayo le-aliphatic, i-alkoxy ibonisa uphawu lwe-nucleophilic kwaye kwezinye iimeko isebenza njengeqela elishiyayo. Olu hlobo lokuziphatha luxhomekeke kakhulu kubunikazi kunye nezinto ezithatha indawo yeqela le-alkyl eliqhotyoshelwe kwi-athomu ye-oxygen. Ekubeni amaqela e-alkoxy engasebenzi kangako, kufuneka i-electrophile enamandla okanye i-catalyst ukuze kuqaliswe ukusabela.
Ngokwahlukileyo koko, amaqela e-acetoxy abonisa ukusabela okwahlukileyo ngenxa yokubakho kwamaqela e-acetyl. I-acetyl moiety kunye ne-partial positive carbon yayo inegalelo kwi-electrophilic nature yeqela le-acetoxy. Ke ngoko, iqela le-acetoxy lithatha inxaxheba ngokukhutheleyo kwi-acetylation reaction, lidlulisela i-acetyl moiety kwezinye iimolekyuli. Ii-acetylation reactions zifumaneka kuyo yonke indawo ekuhlanganisweni kwamayeza, iimveliso zendalo kunye nee-organic compounds ezahlukeneyo.
2. Izitywina ze-alkoxy silicone: Ukukhupha amathuba amatsha
Izitywini ze-alkoxy silicone ziitywini ezenziwe ngokukodwa ezisekelwe kubuchwepheshe bokunyanga i-alkoxy. Ezi zitywini zaziwa ngeempawu zazo ezintle zokubopha kwiintlobo ngeentlobo zezinto ezisetyenziswayo, kubandakanya iglasi, i-ceramics, kunye neeplastiki ezithile. Ukukwazi kwazo ukumelana neemeko ezinzima.amaqondo obushushu aphezulukwayeukumelana nemitha ye-UVZibenza zibe lukhetho lokuqala lokusetyenziswa ngaphandle. Ukongeza, izitywini ze-silicone ze-alkoxylated zilungile kakhuluukumelana nemozulu, ukuqinisekisa iziphumo ezihlala ixesha elide. Ngenxa yaboi-modulus ephantsikunye nokuguquguquka okuphezulu, ziyakwazi ukwamkela iintshukumo zamalungu, nto leyo ezenza zibe zilungele ukusetyenziswa ngokuguquguqukayo. Inzuzo ebalulekileyo ye-alkoxylated silicone sealants kukubaivumba eliphantsingexesha lokunyanga, nto leyo eyenza kube lula ukuyisebenzisa kwiindawo ezivaliweyo.
3. Izitywini zeSilicone zeAcetoxy: Zivavanyiwe kwaye zavavanywa
Kwelinye icala, ii-sealants ze-acetoxy silicone zixhomekeke kubuchwepheshe bokunyanga i-acetoxy. Ezi sealants zisetyenziswe kakhulu kangangeminyaka emininzi kwaye zaziwa ngeempawu zazo zokutywina eziguquguqukayo. Zakha ubudlelwane obuqinileyo nezixhobo zokwakha eziqhelekileyo, kubandakanya iglasi, isinyithi kunye neeseramikhi. Ii-sealants ze-acetoxy silicone zibonakaliswa yiukunyanga ngokukhawulezakwaye igqwesileukumelana nokufumaOlu nyango lukhawulezileyo lwenza imisebenzi ikhawuleze kwaye ibe lula. Nangona kunjalo, qaphela ukuba i-acetoxy silicone sealants inokukhupha ivumba elifana neviniga njengoko iphola, ngoko ke umoya owaneleyo ubalulekile.
4.Khetha isitywina se-silicone esifanelekileyo
Ukuqonda iimpawu ezizodwa zohlobo ngalunye lwe-silicone sealant kubalulekile ekwenzeni isigqibo esinolwazi. Izinto ezinje ngamandla okubopha, amandla okubopha, ixesha lokuphiliswa, ukuguquguquka, ivumba kunye neemfuno ezithile zeprojekthi kufuneka ziqwalaselwe. Apho ukumelana nemisebe ye-UV, amaqondo obushushu aphezulu kunye nemozulu yangaphandle kubalulekile, ii-silicone sealants ze-alkoxylated zihlala zikhethwa. Ii-silicone sealants ze-acetoxy zineepropati zokubola ngokukhawuleza kwaye zilukhetho oluhle kakhulu kwiiprojekthi ezifuna ixesha lokutshintsha ngokukhawuleza kunye ne-bond yokuqala eqinileyo. Kwakhona, kubalulekile ukuqaphela ukuba zombini iintlobo ze-sealant ziyafumaneka ngemibala eyahlukeneyo, zibonelela ngeendlela zobuhle kwizicelo ezifuna ukugqitywa okubonakalayo.
Isiphelo
Xa zizonke, i-alkoxy kunye ne-acetoxy silicone sealants zibonelela ngeenzuzo ezikhethekileyo ngokuxhomekeke kwiimfuno ezithile zeprojekthi. Isigqibo sokugqibela sixhomekeke kwiimpawu zokuncamathelisa, ixesha lokunyanga, ukuguquguquka, ivumba kunye nezinto ezingqongileyo. Ukuqwalasela ulwazi oluvezwe kwezi ndaba, ungakhetha ngokuzithemba i-silicone sealant efanela iimfuno zakho.
Ixesha leposi: Julayi-26-2023