Tanthauzo ndi Kapangidwe ka Ma Polymers
Ma polima ndi ma macromolecule opangidwa ndi mayunitsi ambiri obwerezabwereza, otchedwa ma monomers, olumikizidwa pamodzi ndi ma covalent bonds. Mawu oti "polymer" amachokera ku mawu achigiriki akuti "poly," kutanthauza "ambiri," ndi "meros," kutanthauza "gawo" kapena "gawo." Ma polima akhoza kukhala achilengedwe kapena opangidwa ndi munthu, ndipo amachita gawo lofunikira kwambiri m'mbali zambiri za moyo wathu watsiku ndi tsiku.
M'nkhaniyi, tikambirana za ma polima, magulu awo, kapangidwe kake, ndi mawonekedwe ake enieni ndi a mankhwala omwe amawapangitsa kukhala ofunika kwambiri pa ntchito zosiyanasiyana zamafakitale ndi zamalonda.
Kumvetsetsa Ma polima
Polima ndi mankhwala okhala ndi kapangidwe kake ka molekyulu kakang'ono komwe kamapangidwa ndi kubwerezabwereza kwa mayunitsi ambiri a monomer. Ma monomer ndi mamolekyu ang'onoang'ono omwe amatha kuchitapo kanthu kuti apange mayunitsi obwerezabwereza mu unyolo wa polima. Njira yolumikizira iyi imadziwika kuti polymerization.
Ma polima amatha kugawidwa m'magulu osiyanasiyana monga chiyambi (chachilengedwe kapena chopangidwa), kapangidwe (kolunjika, kokhala ndi nthambi, kapena netiweki), ndi katundu weniweni (thermoset, thermoplastic, kapena elastomer).
1. Ma polima achilengedwe: Zitsanzo zake ndi mapuloteni, cellulose, ndi rabara yachilengedwe. Amapezeka m'chilengedwe ndipo amapangidwa ndi zamoyo kudzera mu njira zamoyo.
2. Ma polymer Opangidwa: Zitsanzo zake ndi monga polyethylene, polypropylene, ndi polyvinyl chloride. Amapangidwa m'ma laboratories kapena m'mafakitale pogwiritsa ntchito njira zopangira polymer.
Kapangidwe ka polima
Ma polima amatha kukhala ndi mitundu yosiyanasiyana ya kapangidwe kamene kamakhudza makhalidwe awo. Mitundu itatu ikuluikulu ya kapangidwe kake ndi yolunjika, yolumikizidwa ndi nthambi, ndi yolumikizana (kapena yokhala ndi magawo atatu).
1. Ma polima a Linear: Mu ma polima a linear, ma monomer amasakanikirana kuti apange maunyolo ataliatali komanso owongoka. Ma polima awa nthawi zambiri amasungunuka mu zosungunulira zina ndipo amakhala ndi mphamvu ya thermoplastic, zomwe zikutanthauza kuti amatha kusungunuka ndikusinthidwa mawonekedwe. Zitsanzo za ma polima a linear ndi monga polyethylene ndi polypropylene.
2. Ma Polima Okhala ndi Nthambi: Mapangidwe a polima okhala ndi nthambi amakhala ndi unyolo waukulu wokhala ndi nthambi zolumikizidwa. Nthambi izi zimakhudza kuchulukana ndi kunyezimira kwa polima. Chitsanzo cha polima wokhala ndi nthambi ndi amylopectin mu starch, yomwe imapereka kukhuthala kochepa mu yankho.
3. Ma polima a netiweki kapena a magawo atatu (3D): Pano, maunyolo a polima amapanga netiweki ya magawo atatu kudzera mu kulumikizana pakati pa maunyolo. Ma polima a netiweki awa nthawi zambiri amakhala olimba, olimba, ndipo sangasungunukenso akapangidwa. Zitsanzo za ma polima a magawo atatu ndi epoxy resin ndi bakelite.
Kugawa Magulu Kutengera Katundu Wathupi
1. Thermoplastics: Ma polima omwe amatha kufewetsedwa ndi kutentha ndi kuuma chifukwa cha kuzizira. Amatha kusinthidwa mobwerezabwereza popanda kutaya zinthu zawo zazikulu. Zitsanzo zake ndi polyethylene ndi polystyrene.
2. Kukonza kutentha: Ma polima awa amasinthasintha mankhwala nthawi zonse akatenthedwa koyamba ndipo sangafewetsedwe potenthedwanso. Nthawi zambiri amakhala olimba komanso opirira kutentha kuposa ma thermoplastic. Zitsanzo za ma thermosets ndi Bakelite ndi melamine.
3. Ma Elastomer: Ma Elastomer ndi ma polima okhala ndi kusinthasintha kwakukulu, omwe amatha kubwerera ku mawonekedwe awo oyambirira pambuyo poti kupsinjika kapena kusintha kwachotsedwa. Rabala lachilengedwe ndi silicone ndi zitsanzo za ma elastomer.
Mankhwala ndi Katundu Wachilengedwe wa Ma polima
Kapangidwe ka mankhwala ndi thupi la ma polima kamakhala ndi gawo lofunikira kwambiri pakutsimikiza momwe amagwiritsidwira ntchito m'mafakitale osiyanasiyana. Kapangidwe kake kofunikira ndi:
1. Kuchulukana: Kumakhudza kulemera ndi mphamvu ya zinthuzo. Ma polima okhala ndi kachulukidwe kochepa nthawi zambiri amakhala opepuka komanso osinthasintha.
2. Malo Osungunula ndi Malo Owira: Kutentha komwe polima imayamba kusungunuka kapena kuwira kumapereka chizindikiro cha kukhazikika kwa kutentha kwa polima.
3. Mphamvu ya Makina: Zimaphatikizapo mphamvu yokoka, kukana kugunda, kuuma, ndi kusinthasintha. Makhalidwe amenewa amatsimikizira kuthekera kwa polima kupirira katundu ndi kupsinjika.
4. Kukana Kutentha ndi Moto: Ma polima ena amapangidwa kuti azitha kupirira kutentha kwambiri popanda kuwola kapena kupsa.
5. Kukana Mankhwala: Kuthekera kwa polima kupirira kuukira kwa mankhwala kuchokera ku zinthu zosiyanasiyana (monga ma acid, alkali, ndi zosungunulira) popanda kusintha mawonekedwe kapena kapangidwe kake.
Mapulogalamu a polima
Chifukwa cha kusiyanasiyana kwa katundu wawo, ma polima amagwiritsidwa ntchito m'njira zosiyanasiyana:
1. Makampani Opanga Mapulasitiki: Ma polima a thermoplastic monga polyethylene ndi polypropylene amagwiritsidwa ntchito popanga zinthu zosiyanasiyana zapulasitiki kuyambira mabotolo ndi matumba mpaka zida zamagalimoto.
2. Zachipatala: Ma polima ogwirizana ndi zinthu zachilengedwe monga polyethylene glycol ndi poly-(lactide-co-glycolide) amagwiritsidwa ntchito pazachipatala monga ma implants, zipangizo zachipatala, ndi mankhwala otulutsidwa nthawi zonse.
3. Nsalu: Ulusi wa polima monga nayiloni, polima, ndi acrylic umagwiritsidwa ntchito popanga nsalu, zovala, ndi zinthu zina za nsalu.
4. Kupaka: Ma polima osinthasintha komanso olimba kwambiri monga polyvinyl chloride (PVC) ndi polyethylene terephthalate (PET) nthawi zambiri amagwiritsidwa ntchito popaka chakudya, zakumwa, ndi zinthu zina zogwiritsidwa ntchito ndi anthu.
5. Zamagetsi: Ma polima oyendetsera magetsi akupangidwa kuti agwiritsidwe ntchito mu zamagetsi osinthasintha, maselo a dzuwa, ndi mabatire.
Pomaliza, ma polima ndi zinthu zamtengo wapatali komanso zogwira ntchito zambiri zomwe zimathandizira ukadaulo ndi zinthu zambiri zomwe timagwiritsa ntchito tsiku lililonse. Ndi kupita patsogolo kwaukadaulo wa ma polima, titha kuyembekezera kuti zinthuzi zipitilizabe kuchita gawo lofunikira pakupanga zatsopano zamafakitale komanso kupita patsogolo kwa anthu.
Kutseka
Ma polima ndi zinthu zochititsa chidwi zokhala ndi mapangidwe ndi makhalidwe osiyanasiyana, zomwe zimathandiza kuti zigwiritsidwe ntchito m'njira zosiyanasiyana, kuyambira mapulasitiki a tsiku ndi tsiku mpaka ukadaulo wapamwamba. Kumvetsetsa bwino kapangidwe ndi makhalidwe a ma polima ndikofunika kwambiri kuti pakhale zatsopano komanso kuti pakhale zipangizo zogwira mtima komanso zokhazikika.
