Te Whakapūhui Tāpiri: Te Tikanga, Ngā Whakamahinga, me Ngā Painga i roto i te Ahumahi
Pendahuluan
Ko te whakapūhui he tauhohenga matū e honoa ai ngā ngota monomer iti hei hanga i ngā macromolecules nui e mōhiotia ana ko ngā polymers. Ko tētahi o ngā momo whakapūhui tino noa ko te whakapūhui tāpiri. Ko te whāinga o tēnei tuhinga he whakamārama i te tikanga taketake o te whakapūhui tāpiri, ōna tono ahumahi nui, me ngā painga e tukuna ana e ia.
Tikanga Whakapūhui Tāpiri
Ko te whakapūhuitanga tāpiri, e mōhiotia ana ko te whakapūhuitanga mekameka, he tukanga e honoa ai ngā monomer me ngā hononga takirua, ngā rōpū mahi tauhohe rānei tetahi ki tetahi mā roto i tētahi raupapa o ngā tauhohenga tāpiri hei hanga i tētahi pūhui. Ka taea te wehewehe i tēnei tukanga kia toru ngā wāhanga matua: te tīmatanga, te horapa, me te whakamutunga.
1. Tīmatanga
Ko te tīmatanga te wāhanga tuatahi o te whakapūhuitanga, ka hangaia ngā rauropi kore utu, ngā katote rānei hei momo tauhohe. Ko ēnei rauropi kore utu ka puta mai i te wetewete wera, i te wetewete whakaahua rānei o ngā mea whakaoho pēnei i ngā peroxide, i ngā matū azo rānei. Hei tauira, i roto i te wetewete o ngā peroxide:
\[ ROOR \rightarrow 2RO\cdot \]
Kātahi ka taea e te rauropi kore utu RO• te tīmata i tētahi tauhohenga me tētahi monomer (hei tauira, ethylene):
\[ RO\cdot + CH_2=CH_2 \rightarrow RO-CH_2-CH_2\cdot \]
2. Te Whakatipu
I te wāhanga whakatipu, ka tauhohe ngā rauropi kore utu i puta i te wāhanga tīmatanga ki ētahi atu monomer hei hanga mekameka polymer roa ake. Ia wā ka tauhohe te rauropi kore utu ki tētahi monomer hou, ka roa ake te mekameka polymer:
\[ RO-CH_2-CH_2\cdot + CH_2=CH_2 \rightarrow RO-CH_2-CH_2-CH_2-CH_2\cdot \]
Ka haere tonu tēnei tukanga kia whakakotahitia rā anō ngā rau ki ngā mano o ngā monomer hei mekameka pūmua roa.
3. Whakamutu
Ko te whakamutu te wāhanga whakamutunga o te whakapūhuitanga ka mutu te tipu o te mekameka pūhui. Ka taea te whakamutu mā roto i ngā tikanga maha, pērā i te whakakotahitanga, te whakakorenga rānei. I roto i te whakakotahitanga, ka honoa ngā rauropi kore utu e rua hei hanga i tētahi ngota pūhui kotahi:
\[ RO-CH_2-CH_2\cdot + \cdot CH_2-CH_2-RO \rightarrow RO-CH_2-CH_2-CH_2-CH_2-RO \]
I roto i te kore taurite, ka whakawhitihia e ngā rauropi kore utu tata ngā ngota hauwai hei whakaputa i ngā ngota kore-māku e rua:
\[ RO-CH_2-CH_2\cdot + \cdot CH_2-CH_2-RO \rightarrow RO-CH_2-CH_3 + CH_2=CH-RO \]
Ngā Whakamahinga o te Tāpiri Polymerization
Ka whakamahia te tukanga tāpiri polymerization hei whakaputa i ngā momo polymer me te whānuitanga o ngā tono puta noa i ngā ahumahi. Ko ētahi o ngā tono matua ko te kirihou, te rapa hangai, me ngā muka.
1. Kirihou
Ko ngā kirihou ngā hua matua o te whakakotahitanga tāpiri. Ko te polyethylene, te polypropylene, te polystyrene, me te polyvinyl chloride (PVC) ngā tauira noa o ngā kirihou i hangaia mā te whakakotahitanga tāpiri:
– Polyethylene (PE): E whakamahia ana i roto i ngā hua o ia rā pērā i ngā putea kirihou, ngā taonga takaro a ngā tamariki, me ngā pounamu inu.
– Polypropylene (PP): E whakamahia whānuitia ana i roto i te hanga taonga whare, takai kai, me ngā wāhanga motuka.
– Polystyrene (PS): Whakamahia hei hanga hua pēnei i ngā ipu kai, ngā taputapu taiwhanga, me te whakamahana.
– Polyvinyl chloride (PVC): Whakamahia ana mō te hanga paipa, taura, me ngā rauemi hanga.
2. Rapa Hangaia
Ka hangaia hoki ngā rapa hangai pērā i te polibutadiene me te styrene-butadiene (SBR) mā te tāpiritanga polymerization. Ka whakamahia ēnei rapa hangai ki te hanga potae waka, kapu hu, me ētahi atu hua rapa.
3. Muka
Ko ētahi muka hangai e whakamahia ana i roto i te umanga kakahu ka hangaia mā te tāpiri polymerization. Ko ētahi tauira ko te kiriaku me te polypropylene, e whakamahia ana i roto i te hanga kakahu, whāriki, me ētahi atu kakahu.
Ngā Painga o te Tāpiritanga Polymerization
He maha ngā painga o te tāpiritanga polymerization e tino whai hua ai i roto i ngā tono ahumahi.
1. Te Whai Hua o te Whakaputa
Mā te tāpiritanga polymerization ka taea te whakaputa i ngā polymer nui me te whakahaere pai i te roa o te mekameka me te tohatoha taumaha ngota. He tere, he ngāwari hoki te whirihora i te tukanga, me ngā āhuatanga ka taea te whakarerekē hei whakaputa i te whānuitanga o ngā polymer.
2. Utu iti
He iti te utu o ngā monomer e whakamahia ana hei tāpiri i te polymerization, ā, he whānui te wātea. Hei tāpiri, ka taea te whakahaere i tēnei tikanga me te iti o te whakapaunga pūngao, ka whai wāhi atu ki te whai huatanga utu whānui o te tukanga whakaputa.
3. Te Whānuitanga o ngā Rauemi
Mā te tāpiritanga polymerization ka puta he polymer me te whānuitanga o ngā āhuatanga ā-tinana me ngā āhuatanga ā-pūkaha. Mā te whakarerekē i te momo monomer, mā te whakarerekē rānei i ngā tikanga tauhohenga, ka taea e ngā kaihanga te waihanga polymer e hāngai ana ki ngā hiahia motuhake.
4. Te Pūmau me te Tūturutanga
Ko ngā pūmua i hangaia mā te tāpiritanga pūmua he tino ātete ki ngā āhuatanga taiao maha, tae atu ki te pāmahana, te matū, me te ahotea ā-tinana. Nā tēnei ka tino pai mō ngā tono e hiahia ana kia roa te mau, pērā i ngā rauemi hanga me ngā taputapu ahumahi.
5. Tukurua
He maha ngā pūhui tāpiri, pērā i te polyethylene me te polypropylene, ka taea te hangarua, e tautoko ana i ngā mahi tauwhiro me te whakaiti i ngā para taiao. He mea nui rawa tēnei i te mea kei te tipu haere te mōhiotanga ki te pānga taiao o ngā para kirihou.
Ngā Wero me ngā Otinga
Ahakoa ngā painga maha e tukuna ana e ia, he maha ngā wero kei mua i te whakapūhuitanga tāpiritanga me aro atu ki te whakapai ake i tōna whai huatanga me tōna pumau.
1. Te Whakahaere i ngā Āhuatanga o te Polymer
He uaua te whakahaere i te hanganga me ngā āhuatanga o ngā pūmua ka puta mai. Me whakawhanake tonu ngā kairangahau i ngā tikanga hei whakahaere i te tohatoha taumaha ngota me te whirihoranga ā-ira matū kia tutuki ai te mahi tino pai.
2. Pānga ki te Taiao
He maha ngā pānga nui ki te taiao o te hanga pūmua. Me whakapai tonu te whakamahinga rauemi whai hua me ngā hangarau e pai ana ki te taiao hei whakaiti i te tapuwae waro o ngā tukanga hanga pūmua.
3. Ngā Mahi Whakamahi Anō
He mea nui te whakawhanake i ngā hangarau hangarua whai hua, whai hua hoki mō te whakahaere i te nui haere o ngā para polymer. Tērā pea he wāhi nui te whakapai ake i te wehewehe me te tukatuka i ngā para kirihou ki tēnei mahi.
Whakamutunga
He mea nui te tāpiritanga polymerization i roto i te hanga i te whānuitanga o ngā polymer e tautoko ana i ngā āhuatanga maha o te ao hou. Mai i ngā kirihou me te rapa ki ngā muka kakahu, mā tēnei tikanga ka taea te hanga rauemi whai hua me te utu tika. Ahakoa he wero kei mua, ka taea e ngā whanaketanga hangarau me te rangahau te wikitoria i ēnei arai me te whakanui ake i ngā painga o te tāpiritanga polymerization. Mā te whanaketanga tonu o ngā tono me te arotautanga tukanga, ka noho tonu te tāpiritanga polymerization hei wāhanga nui i roto i ngā ahumahi matū me te hanga, hei tautoko i te whanaketanga ki tētahi hapori pumau ake.
