Ndi chitukuko chosalekeza cha sayansi ndi ukadaulo,mapulasitiki a polimaachita bwino kwambiri, kupanga zida zomangira za anthu ndi zida zokhalamo zozikidwa pazovuta komanso mwachangu mpaka zofewa.
1.Tanthauzo
Zigawo zazikulu zamapulasitiki a polimamakamaka ma polima, omwe kulemera kwake kwa molekyulu kumakhala pafupifupi 1,000, komwe kumangokhala kwamalingaliro akuthupi.Pakali pano, mapulasitiki polima chimagwiritsidwa ntchito, koma ntchito tsiku ndi tsiku pulasitiki ndi apanga ndi polima mankhwala, kawirikawiri amatchedwa mkulu kapena macromolecule, ndi apanga ndi monomer zopangira kapena zopangira mu zipangizo Integrated, ndipo mwa chitukuko kenako, ndi maphatikizidwe utomoni, mtundu, stabilizer ndi zina zowonjezera.Maonekedwe a pulasitiki ya polima amatha kusinthidwa momasuka ndipo akhoza kupangidwa molingana ndi zomwe wogwiritsa ntchito akufuna.
2.Makhalidwe
Mapulasitiki a polima samangokhala ndi zosiyana zawo zokha, ndiko kuti, kusintha kosasintha kwa mawonekedwe, komanso kukhala ndi viscoelasticity.Polima pulasitiki, ngati pansi mphamvu kunja, thupi lake adzatulutsa mkulu zotanuka mapindikidwe, viscous otaya, polima pulasitiki mapindikidwe makamaka zokhudzana ndi nthawi.Komanso, polima pulasitiki alinso mkulu mphamvu yeniyeni, mphamvu otsika ndi makhalidwe ena, mphamvu ya pulasitiki polima zambiri m'munsi, koma kachulukidwe ake ndi otsika, kotero mphamvu amakhala apamwamba.Polima ali ndi makhalidwe ambiri, monga bata mkulu, mkulu kuvala kukana, kukulitsa, kutchinjiriza mkulu, choncho chimagwiritsidwa ntchito m'madera osiyanasiyana, ndi kukomera anthu ambiri.
Mitundu ya mapulasitiki a polima nawonso ndi osiyanasiyana.Pakali pano, gulu la mapulasitiki polima ku China makamaka zikuphatikizapo magulu asanu ndi awiri: mphira, zokutira polima, zipangizo polima, nsanganizo masanjidwewo, mapulasitiki, ulusi ndi mapulasitiki.
a.Mpira.
Mtengo wa unyolo wamamolekyu a mphira ndi wocheperako, wosinthika, izi zikuchokera pakuwona gawo la sayansi.Rubber ndi kukula kwa mphamvu yakunja idzasintha mawonekedwe ake, ndi kusakhazikika, ngati mphamvu yakunja itachotsedwa, chikhalidwe choyambirira cha mphira chikhoza kubwezeretsedwa mwamsanga.
b.Zomatira polima.
Zida zomatira za zomatira za polima ndizophatikiza zachilengedwe.Pochita, nthawi zambiri amagawidwa m'mitundu iwiri: zomatira zachilengedwe, zopangira.Chogwiritsidwa ntchito kwambiri ndi zomatira zopangira.
c.zokutira polima.
Zigawo zazikulu za zokutira za polima zimakhala makamaka ma polima, omwe amapangidwa m'njira yosavuta, makamaka kuwonjezera zosungunulira kapena zowonjezera pakupanga kwake.Kupaka polima kumagawidwa m'mitundu itatu nthawi zambiri, yomwe ndi mafuta, utomoni wopangira ndi utomoni wachilengedwe, womwe umagwiritsidwa ntchito nthawi zambiri pamoyo watsiku ndi tsiku.
d.zinthu za polima.
Zomwe zimagwiritsidwa ntchito nthawi zambiri zimakhala ndi ma enzyme apamwamba kwambiri komanso zinthu zowonekera kwambiri.Zida za polima zimakhala ndi ntchito zina: mphamvu, zinthu, kutembenuka kwa chidziwitso, kufalitsa ndi maginito.
e.fiber.
Ulusi umakhala wofala m'moyo watsiku ndi tsiku, nthawi zambiri umagawidwa m'mitundu iwiri: ulusi wachilengedwe ndi ulusi wamankhwala.Ulusi uli ndi mawonekedwe amphamvu yaing'ono yopindika, mphamvu yaying'ono yachiwiri ya valence ndi modulus yayikulu pamalingaliro akuthupi.
f.Pulasitiki.
Pulasitiki ndi mtundu wazinthu zomwe AMAGWIRITSA NTCHITO zambiri pakadali pano, komanso kukhala zinthu wamba.Zigawo zazikulu za mapulasitiki nthawi zambiri zimakhala ma resin opangidwa, ma polima achilengedwe, ndi kuphatikiza zina zowonjezera, monga pulasitiki, zodzaza ndi zina zotero.Pulasitiki nthawi zambiri imakhala yopangidwa ndi utomoni wopangidwa, kotero imatha kugawidwa m'mapulasitiki a thermosetting, thermoplastic.
3. Zinthu zakuthupi
Ambiri, ngati pulasitiki polima anaika zinthu isothermal, zosavuta kupanga mankhwala.Mu processing kwenikweni, kutentha kwa crystallization sikugwirizana kwathunthu.Ngati kusiyana kwa kutentha kwa crystallization kuli kwakukulu, kudzakhudza ndondomeko ya crystallization.Panthawi imodzimodziyo, kupanikizika kwakukulu kumapangidwa nthawi zambiri pozungulira kupanga, filimu yotambasula kupanga ndi kupanga extrusion, zomwe zimabweretsa chizolowezi chofulumizitsa mankhwala.Kuphatikiza apo, mapulasitiki amagwiritsa ntchito njira zometa ubweya.Ndipo chifukwa cha kupsinjika kwamphamvu, kusungunulako kumapanga makhiristo a ulusi wautali.Kuchuluka kwa kupsinjika maganizo ndi kupsinjika maganizo kumakhala, unyolo umakhala wautali kwambiri ndipo umasungunuka kwambiri.
4. Mankhwala katundu
Nthawi zambiri, ngati mapulasitiki a polima ayikidwa muzovuta kwambiri komanso kutentha kwambiri, kapangidwe kake kamakhala ndi zosintha zina.Pochita izi, mapulasitiki a polima nthawi zambiri amatulutsa zinthu zambiri zowonongeka, motero amatulutsa zinthu zovulaza kwambiri.Kuti zimenezi zitheke, mu processing ayenera zomveka zopangira zizindikiro, kusankha apamwamba zipangizo.Pa nthawi yomweyi, kachulukidwe kakang'ono ka antioxidant ndi stabilizer akhoza kuwonjezeredwa mu ndondomeko kuti apititse patsogolo ntchito yotsutsana ndi kuwonongeka kwa polima.
Nthawi yotumiza: Jul-16-2019