Machena, akajeka, akapfava, uye akachena, anofananidzira kuchena.
Vanhu vazhinji vanofarira zvinhu zvichena, uye zvinhu zvevatengi zvinowanzogadzirwa muchena.Kazhinji, vanhu vanotenga zvinhu zvichena kana kupfeka hembe chena vachangwarira kuti chena risawana mavara.Asi kune rwiyo runoti, "Munyika ino iripo, ramba zvachose."Hazvina mhosva kuti wakaedza zvakadini kuchengetedza zvinhu izvi kuti zvisasvibiswa, zvinoshanduka zvishoma nezvishoma pachezvazvo.Kwevhiki, gore, kana makore matatu, unopfeka headphone kesi kushanda zuva rega rega, uye hembe chena yausina kupfeka muwadhiropu chinyararire inoshanduka yero wega.
Muchokwadi, kutsvuka kweshinda dzembatya, masosi eshangu dzakarasika, uye mabhokisi eheadphones epurasitiki chiratidzo chekuchembera kwepolymer, kunozivikanwa seyero.Yellowing inoreva chiitiko chekushatisa, kurongazve, kana kuyambuka-kubatanidza mumamorekuru ezvigadzirwa zvepolymer panguva yekushandiswa, zvichikonzerwa nekupisa, mwenje wemwaranzi, oxidation, uye zvimwe zvinhu, zvichikonzera kuumbwa kwemamwe mapoka emavara anoshanda.
Aya mapoka ane mavara anowanzova kabhoni kabhoni kaviri bonds (C=C), carbonyl mapoka (C=O), imine mapoka (C=N), zvichingodaro.Kana iyo nhamba ye conjugated carbon carbon double bonds inosvika 7-8, inowanzoita yero.Kazhinji, kana iwe ukaona kuti zvigadzirwa zvepolymer zvava kutanga kushanduka yero, chiyero cheyero chinowedzera kuwedzera.Izvi zvinodaro nekuti kuderedzwa kwemapolymers kuita kweketani, uye kana maitiro ekudzikisira atanga, kuparara kwemamorekuru cheni kwakafanana nedomino, nechikamu chimwe nechimwe chinodonha chimwe nechimwe.
Kune nzira dzakawanda dzekuchengeta zvinhu zvichena.Kuwedzera titanium dioxide uye fluorescent whitening agents zvinogona kunyatso wedzera kuchena kwechinyorwa, asi hazvigone kudzivirira zvinhu kubva pakutsvuka.Kuti udzikise kutsvuka kwemapolymers, zvigadziriso zvemwenje, zvinyoro zvinyoro, quenching agents, nezvimwe zvinogona kuwedzerwa.Aya marudzi ezviwedzere anogona kutora simba rinotakurwa nechiedza cheultraviolet muchiedza chezuva, zvichidzosa iyo polymer kune yakagadzikana.Uye anti thermal oxidants inogona kubata iyo yemahara radicals inogadzirwa neoxidation, kana kuvharira kuderedzwa kwemaketani epolymer kumisa kuita kweketani kwekuparara kwepolymer cheni.Zvishandiso zvine hurefu hwehupenyu, uye zvinowedzerwa zvinewo hupenyu.Kunyangwe zvekuwedzera zvinogona kudzikamisa chiyero chepolymer yellowing, ivo pachavo vanozokundikana zvishoma nezvishoma panguva yekushandiswa.
Pamusoro pekuwedzera zvinowedzera, zvakare zvinokwanisika kudzivirira polymer yellowing kubva kune zvimwe zvinhu.Semuenzaniso, kuderedza kushandiswa kwezvinhu mukupisa kwepamusoro uye kupenya kwekunze kwekunze, zvakakosha kuisa chiedza chinotora chiedza kune zvigadzirwa paunenge uchizvishandisa kunze.Yellowing haingokanganisa chitarisiko chete, asi inoshandawo sechiratidzo chezvinhu zvemechanise kuita degradation kana kutadza!Kana zvinhu zvekuvaka zvichiitwa yero, zvitsva zvinotsiva zvinofanirwa kutsiviwa nekukasira.
Nguva yekutumira: Zvita-20-2023