Mibvunzo yeMienzaniso & Kukurukurirana kweMhando dzePolymers
Polymer imorekuru hombe inoumbwa nemayuniti madiki anonzi mamonomers. Mapolymer anoshandiswa mumhando dzakasiyana-siyana, kubva kumapurasitiki nerabha kusvika kumafiber ekugadzira nezvinhu zvekuvaka. Kunzwisisa mapolymer kwakakosha mukemistri, sainzi yezvinhu, uye maindasitiri akasiyana-siyana. Chinyorwa chino chichakurukura mienzaniso yakati wandei yezvinetso maererano nemarudzi emapolymer uye kupa mhinduro dzakadzama kumatambudziko aya.
Mibvunzo yemuenzaniso nekukurukurirana
Mubvunzo 1:
Dudzai mhando nhatu dzemapolymers zvichibva pamavambo adzo uye mupe muenzaniso weimwe neimwe.
Kukurukurirana:
1. MaPolymer echisikigo:
Mapolymer echisikigo mapolymer anowanikwa zvakasikwa munharaunda. Mienzaniso yemapolymer echisikigo inosanganisira:
– Cellulose: Inowanikwa mumadziro emasero emiti.
– Rabha yechisikigo: Inowanikwa kubva mumuto wemuti weHevea brasiliensis.
– Mapuroteni: Akadai secollagen inowanikwa muganda nenyama yemhuka.
2. MaPolymer Ekugadzira:
Mapolymer ekugadzira zvinhu mapolymer akagadzirwa nevanhu kuburikidza nemaitiro emakemikari ekugadzira. Mienzaniso yemapolymer ekugadzira zvinhu inosanganisira:
– Polyethylene (PE): Inoshandiswa mukugadzira mabhegi epurasitiki.
– Polypropylene (PP): Inoshandiswa muindasitiri yemotokari uye mumapakeji ezvekudya.
– Polyvinyl Chloride (PVC): Inoshandiswa mukugadzira mapaipi netambo.
3. MaPolymer asina kugadzirwa:
Mapolymers emhando ye semi-synthetic anoshandiswa pakugadzirisa mapolymers echisikigo kuti avandudze hunhu hwavo. Mienzaniso yemapolymers emhando ye semi-synthetic inosanganisira:
– Cellulose Acetate: Yakagadzirwa kubva kucellulose yakagadziriswa uchishandisa acetic acid, inoshandiswa mufirimu yemifananidzo.
– Nitrocellulose: Inowanikwa kuburikidza ne nitration ye cellulose, inoshandiswa mukugadzira zvinoputika uye machira.
Mubvunzo 2:
Tsanangura musiyano uripo pakati pemapolymer ethermoplastic nethermoset, wopa mienzaniso miviri yeimwe neimwe.
Kukurukurirana:
1. MaPolymer eThermoplastic (Thermoplastics):
Iyi polymer inopfava kana yapiswa uye inooma kana yatonhodzwa, uye inogona kuitwa nenzira iyi kakawanda. Izvi zvinoita kuti zvive nyore kudzokorodza. Semuenzaniso:
– Polyethylene (PE): Inoshandiswa mukugadzira mabhegi epurasitiki nemabhodhoro.
– Polystyrene (PS): Inoshandiswa mukugadzira zvinhu zvinodzivirira kupisa uye kurongedza chikafu.
2. MaPolymer eThermosetting (Thermosets):
Mapolymer aya, kana angogadzirwa kuburikidza nekupisa nekutonhodza, haagoni kunyungudutswa zvakare. Ane chimiro chakasimba uye haagone kudzokororwazve nenzira imwecheteyo seye thermoplastics. Semuenzaniso:
– Bakelite: Inowanikwa mumaswichi emagetsi uye mumapambo emidziyo yekubikira.
– Epoxy: Inoshandiswa mumaglues, coatings, uye composites dzinogara kwenguva refu.
Mubvunzo 3:
Tsanangura maitiro ekuwedzera polymerization uye ipa mienzaniso yemapolymers akagadzirwa kuburikidza nemaitiro aya.
Kukurukurirana:
Kuwedzera polymerization inzira yekugadzira mapolymer kuburikidza ne chain reaction umo ma monomers ane double bonds (kazhinji carbon-carbon double bonds) anobatana pasina kugadzira zvimwe zvigadzirwa.
Matanho ekuwedzera polymerization anosanganisira:
1. Kutanga: Kuumbwa kwemafree radicals kana maion anotanga reaction.
2. Kupararira: Mafree radicals kana maion anoita zvakafanana nemamonomers, zvichigadzira cheni refu dzepolymer.
3. Kuguma: Kuguma kwemaitiro acho kunopera kana ma free radicals maviri akabatana.
Mienzaniso yemapolymer ekuwedzera:
– Polyethylene (PE): Yakagadzirwa kubva ku ethylene monomer (C2H4).
– Polypropylene (PP): Yakagadzirwa kubva kupropylene monomer (C3H6).
Mubvunzo 4:
Zvinorevei ne condensation polymerization uye ipai mienzaniso miviri yema polymers akagadzirwa kuburikidza nemaitiro aya.
Kukurukurirana:
Kugadziriswa kwemvura (condensation polymerization) inzira ye polymerization umo ma monomers anobatana nekubvisa mamorekuru madiki akadai semvura kana methanol.
Mienzaniso ye condensation polymerization ndeiyi:
1. Kugadzirwa kweNylon:
Nylon 6,6 inoumbwa kuburikidza nekuita pakati pehexamethylenediamine neadipic acid, zvichigadzira mvura sechinhu chinobva pairi.
\[ \chinyorwa{H}_2\chinyorwa{N}-(\chinyorwa{CH}_2)_6\chinyorwa{NH}_2 + \chinyorwa{HOOC}-(\chinyorwa{CH}_2)_4\mavara{COOH} \kurudyi (-\text{NH}-(\text{CH}_2)_6\text{NH-CO}-(\) COOH}__zvinyorwa \zvinyorwa{H}_2\zvinyorwa{O} \]
2. Kugadzirwa kwePolyester:
Mapolyester akadai sepolyethylene terephthalate (PET) anoumbwa kuburikidza nekuita pakati peterephthalic acid ne ethylene glycol, zvichigadzira mvura sechinhu chimwe chete.
\[ \chinyorwa{HOOC-}\chinyorwa{C}_6\chinyorwa{H}_4\chinyorwa{COOH} + \chinyorwa{HO-CH}_2\chinyorwa{CH}_2\chinyorwa{OH} \museve wekurudyi (-\text{O-CH}_2\text{CH}_2-\text{OCO-}\text{C}_6\text{H}_4)__text{H}_4 \zvinyorwa{H}_2\zvinyorwa{O} \]
Mubvunzo 5:
Hunhu hwemapolymer hunogona sei kuchinjwa nekushandisa mapurasitiki? Ipa muenzaniso.
Kukurukurirana:
Mapurasitiki zvinhu zvinowedzerwa kumapolymer kuti zviwedzere kuchinjika, kuderedza kuputsika, uye kuderedza tembiricha yekuchinja kwegirazi (Tg). Mapurasitiki anoshanda nekuderedza simba remabond epakati pemamorekuru mukati mepolymer, zvichibvumira cheni dzepolymer kufamba zvakasununguka uye kuwedzera kuputsika kwezvinhu.
Mienzaniso yekushandisa mapurasitiki:
– PVC nemapurasitiki: Mukugadzira tambo dzemagetsi, PVC inosanganiswa nemapurasitiki akadai sephthalates kuti iite kuti igare kwenguva refu uye ichichinjika.
– Cellulose acetate uye plasticizers: Zvinoshandiswa mukugadzira mafirimu uye lacquers kuti zvigadzirwa zvisanyanya kuomarara.
Mhedziso
MaPolymer zvinhu zvinoshanduka-shanduka zvinoshamisa zvine basa guru muhupenyu hwezuva nezuva uye tekinoroji yemazuva ano. Nekunzwisisa mhando dzemapolymer uye maitiro epolymerization, tinogona kugadzira zvinhu zvitsva zvine hunhu hunodiwa uye kuwedzera mashandisirwo azvo muminda yakasiyana-siyana. Dzidzo yePolymer inotanga nekugadzirisa nyaya idzi uye kuwana kunzwisisa kwakadzama kwenheyo dzakakosha dziri musainzi yepolymer. Chinyorwa chino chine chinangwa chekupa kunzwisisa kwekutanga kwemhando dzepolymer uye kukurudzira vaverengi kuti varambe vachidzidza uye vachiongorora zvakadzama nezvemapolymer uye mashandisirwo awo.
