Polyvinyl utywala PVA

I-Polyvinyl alcohol (PVA) i-polymer yokwenziwa ephuma kwi-vinyl acetate ngokusebenzisa i-polymerization kunye ne-hydrolysis elandelayo. I-polymer e-soluble yamanzi kunye noluhlu olubanzi lwezicelo ngenxa yeempawu zayo ezizodwa. Makhe sihlolisise imiba ephambili ye-polyvinyl alcohol:

1. Ubume beMichiza: Utywala bePolyvinyl lubonakaliswe yiyunithi ephindaphindiweyo ye-vinyl alcohol monomers. Iiyunithi zotywala zevinyl zidityaniswe kunye ne-carbon-carbon bond eyodwa, zenza ikhonkco yepolymer ehambelanayo. Nangona kunjalo, utywala obusulungekileyo be-vinyl abuzinzile, ngoko ke utywala lwe-polyvinyl luveliswa yi-hydrolysis ye-polyvinyl acetate, apho amanye amaqela e-acetate athatyathwa ngamaqela e-hydroxyl.

2. Iinkcazelo ngeempawu:

• Ukunyibilika kwamanzi: Enye yezona zinto zibalulekileyo zePVA kukunyibilika kwayo okuphezulu emanzini. Ichithwa ngokukhawuleza emanzini ukwenza izisombululo ezicacileyo, ezicacileyo, okwenza ukuba zilungele izicelo ezahlukeneyo apho ukuqulunqwa kwamanzi kuyadingeka.
• Amandla okwenza iFilimu: I-PVA inokwenza iifilimu ezicacileyo, eziguquguqukayo xa zikhutshwe kwisisombululo sayo samanzi. Ezi filimu zinamandla afanelekileyo omatshini, iimpawu zokuthintela, kunye nokubambelela kwii-substrates, ezizenza zibe luncedo kwizicelo ezifana neengubo, izinto zokuncamathelisa, kunye nezinto zokupakisha.
• I-Biocompatibility: I-PVA ngokubanzi ithathwa njenge-biocompatible kunye ne-non-toxic, iyenza ifaneleke ukusetyenziswa kwizicelo ezahlukeneyo zonyango kunye namayeza, njengeenkqubo zokuhanjiswa kweziyobisi, ukubopha amanxeba, kunye ne-scaffolds zobunjineli bezicubu.
• Ukuzinza kweMichiza: I-PVA ibonisa ukuzinza kakuhle kweekhemikhali, ukuchasa ukuthotywa kwe-acids, iziseko, kunye ne-solvents eziphilayo phantsi kweemeko eziqhelekileyo. Nangona kunjalo, inokuthi iqhube i-hydrolysis phantsi kweemeko ze-acidic okanye i-alkaline, ekhokelela ekulahlekelweni kweepropati.

3. Ukusetyenziswa: I-Polyvinyl alcohol inoluhlu olubanzi lwezicelo kuwo wonke amashishini ahlukeneyo:

• I-Adhesives: I-PVA-based adhesives isetyenziswa ngokubanzi kwi-woodworking, i-paperboard packaging, kunye neemveliso zabathengi ngenxa yokubambelela kakuhle, ukumelana kwamanzi, kunye nokulula ukusetyenziswa.
• Ilaphu: Iintsinga zePVA zisetyenziselwa ukufakwa kwelaphu ukunika amandla, ukunganyangeki kwe-abrasion, kunye nokuzinza komda kwilaphu.
• Ukupakishwa: Iifilimu ezisekelwe kwi-PVA zisetyenziswa njengezinto zokupakisha zokutya, amayeza, kunye nezinye iimveliso ngenxa yeempawu zabo zokuthintela kunye nokubola kwezinto eziphilayo.
• Iingubo zePhepha: Iingubo ezisekelwe kwi-PVA zifakwe kwiphepha kunye nebhodi lephepha ukuze kuphuculwe ukugudiswa komhlaba, ukuprintwa, kunye nokuxhathisa ukufuma.
• Ulwakhiwo: Ulwakhiwo olusekwe kwiPVA lusetyenziswa kwimathiriyeli yokwakha enje ngemixube yesamente, izongezo zesamente, kunye nezilungisi zodaka ukunyusa ukusebenza, ukuncamathelisa, kunye nokuqina.

4. Iingqwalasela zokusiNgqongileyo: Ngelixa utywala obuyipolyvinyl bunokubola phantsi kweemeko ezithile, ukusetyenziswa kwabo ngokubanzi kunye nokulahlwa kwabo kusenokuba neempembelelo zokusingqongileyo. I-Biodegradation ye-PVA ngokuqhelekileyo yenzeke ngokusebenzisa i-microbial action kwindawo e-aerobic, efana neendawo zokuvundisa okanye iindawo zokucocwa kwamanzi amdaka. Nangona kunjalo, kwiindawo ezihlala i-anaerobic, ezinjengendawo yokulahla inkunkuma, i-PVA inokuqhubeka ixesha elide. Iinzame zokuphuhlisa izinto ezizezinye ezinokubola okanye ezivuselelekayo kwimixube yePVA yesintu ziyaqhuba ukuthomalalisa oku kukhathazeka kokusingqongileyo.

Isishwankathelo, i-polyvinyl alcohol (PVA) i-polymer eguquguqukayo enoluhlu olubanzi lwezicelo ngenxa yokunyibilika kwamanzi, amandla okwenza ifilimu, i-biocompatibility, kunye nokuzinza kweekhemikhali. Ukusetyenziswa kwayo kubanzi kumashishini afana nokuncamathelisa, amalaphu, ukupakisha, ukugquma kwamaphepha, nezinto zokwakha. Ngelixa i-PVA ibonelela ngeenzuzo ezininzi, ukuqwalaselwa kokusingqongileyo kunye neenzame zokuphuhlisa ezinye iindlela ezizinzileyo zizinto ezibalulekileyo ekuqhubekeni kokusetyenziswa kunye nophuhliso.