Zipangizo zokutira za polyurethane zimatha kukhala zachikasu pakapita nthawi chifukwa chowonekera kwa nthawi yayitali ku kuwala kwa ultraviolet kapena kutentha, zomwe zimakhudza mawonekedwe awo komanso moyo wawo wautumiki. Poyambitsa UV-320 ndi 2-hydroxyethyl thiophosphate mu unyolo wowonjezera wa polyurethane, polyurethane yopanda madzi yopanda chikasu yolimbana ndi chikasu inakonzedwa ndikuyika pa zokutira zachikopa. Kupyolera mu mtundu kusiyana, bata, kupanga sikani maikulosikopu elekitironi, X-ray sipekitiramu ndi mayesero ena, anapeza kuti okwana mtundu kusiyana △E chikopa ankachitira ndi mbali 50 ya nonionic madzi ofotokoza polyurethane ndi kukana kwambiri chikasu anali 2.9, kusintha mtundu kalasi anali 1 kalasi, ndipo panali kusintha pang'ono chabe mtundu. Kuphatikizidwa ndi zizindikiro zoyambira zogwirira ntchito zamphamvu zolimba zachikopa komanso kukana kuvala, zikuwonetsa kuti polyurethane yosagwira chikasu imatha kupititsa patsogolo kukana kwachikopa kwachikopa ndikusunga mawonekedwe ake amakina komanso kukana kuvala.

Pamene moyo wa anthu wapita patsogolo, anthu ali ndi zofunika zapamwamba pamipando yachikopa, zomwe zimangofuna kuti zikhale zosavulaza thanzi laumunthu, komanso zimafuna kuti zikhale zokondweretsa. Polyurethane yopangidwa ndi madzi imagwiritsidwa ntchito kwambiri muzovala zachikopa chifukwa chachitetezo chake chabwino komanso chosaipitsa, gloss yapamwamba, ndi mawonekedwe a amino methylidynephosphonate ofanana ndi chikopa. Komabe, polyurethane yopangidwa ndi madzi imakonda kukhala yachikasu pansi pa mphamvu ya nthawi yayitali ya kuwala kwa ultraviolet kapena kutentha, zomwe zimakhudza moyo wautumiki wa zinthuzo. Mwachitsanzo, zipangizo zambiri za nsapato zoyera za polyurethane nthawi zambiri zimawoneka zachikasu, kapena zazikulu kapena zochepa, padzakhala chikasu pansi pa kuwala kwa dzuwa. Chifukwa chake, ndikofunikira kuphunzira kukana kwachikasu kwa polyurethane yamadzi.

Pakali pano pali njira zitatu zowonjezeretsa kukana kwachikasu kwa polyurethane: kusintha chiwerengero cha zigawo zolimba ndi zofewa ndikusintha zipangizo kuchokera kuzomwe zimayambitsa, kuwonjezera zowonjezera organic ndi nanomaterials, ndi kusintha kwapangidwe.

(a) Kusintha chiwerengero cha zigawo zolimba ndi zofewa ndi kusintha zopangira angathe kuthetsa vuto la polyurethane lokha sachedwa chikasu, koma sangathe kuthetsa chikoka cha chilengedwe kunja pa polyurethane ndipo sangathe kukwaniritsa zofunika msika Kudzera TG, DSC, kukana abrasion ndi kumakokedwa kuyezetsa, anapeza kuti katundu thupi la okonzeka nyengo zosagwira polyurethane ndi polyurethane koyera ndi zikopa zotsukidwa ndi polyurethane chikopa choyera ndi chikopa, DSC. Polyurethane yosagwira nyengo imatha kukhalabe ndi zikopa zoyambira pomwe imathandizira kwambiri kupirira kwanyengo.

(b) Kuphatikizika kwa zowonjezera za organic ndi nanomatadium kumakhalanso ndi zovuta monga kuchuluka kwachulukidwe komanso kusakanizika bwino kwa thupi ndi polyurethane, zomwe zimapangitsa kuchepa kwa makina a polyurethane.

(c) Zomangira za disulfide zimakhala ndi kusinthika kwamphamvu, zomwe zimapangitsa mphamvu yawo yotsegulira kukhala yotsika kwambiri, ndipo imatha kuthyoledwa ndikumangidwanso kangapo. Chifukwa cha kusinthika kwamphamvu kwa ma bond a disulfide, zomangirazi zimasweka nthawi zonse ndikumangidwanso pansi pa kuwala kwa kuwala kwa ultraviolet, kutembenuza mphamvu ya kuwala kwa ultraviolet kukhala kutulutsa mphamvu ya kutentha. Kutentha kwa polyurethane kumachitika chifukwa cha kuwala kwa kuwala kwa ultraviolet, komwe kumapangitsa kuti zinthu ziziyenda bwino muzinthu za polyurethane ndikupangitsa kuti ma bond cleavage ndi kukonzanso zinthu zisinthe, zomwe zimapangitsa kusintha kwamapangidwe ndi chikasu cha polyurethane. Chifukwa chake, poyambitsa zomangira za disulfide m'magawo am'madzi opangidwa ndi polyurethane, mphamvu yodzichiritsa yokha komanso yachikasu ya polyurethane idayesedwa. Malinga ndi mayeso a GB/T 1766-2008, △E inali 4.68, ndipo kalasi yosintha mtundu inali giredi 2, koma popeza idagwiritsa ntchito tetraphenylene disulfide, yomwe ili ndi mtundu wina, siyoyenera ku polyurethane yosagwira chikasu.

Zoyatsira kuwala kwa ultraviolet ndi disulfides zimatha kusintha kuwala kwa ultraviolet kukhala kutulutsa mphamvu ya kutentha kuti muchepetse mphamvu ya kuwala kwa ultraviolet pamapangidwe a polyurethane. Poyambitsa chinthu chosinthika cha 2-hydroxyethyl disulfide mu polyurethane synthesis exthesis siteji, imalowetsedwa mu polyurethane, yomwe ndi disulfide pawiri yomwe ili ndi magulu a hydroxyl omwe ndi osavuta kuchita ndi isocyanate. Kuphatikiza apo, chotsitsa cha UV-320 cha ultraviolet chimayambitsidwa kuti chigwirizane ndi kusintha kwa kukana kwachikasu kwa polyurethane. UV-320 yokhala ndi magulu a hydroxyl, chifukwa cha mawonekedwe ake osavuta kuchita ndi magulu a isocyanate, imathanso kulowetsedwa m'magawo a polyurethane ndikugwiritsidwa ntchito pakati pa chikopa chapakati kuti chithandizire kukana kwachikasu kwa polyurethane.

Kupyolera mu mayeso kusiyana mtundu, anapeza kuti chikasu kukana wa yellow kukana polyureth Kudzera TG, DSC, abrasion kukana ndi kumakanika kuyezetsa, anapeza kuti katundu thupi la okonzeka nyengo zosagwira polyurethane ndi zikopa ankachitira ndi polyurethane koyera zinali zogwirizana, kusonyeza kuti nyengo zosagwira polyurethane akhoza kukhalabe ndi zinthu zofunika za chikopa pamene kwambiri kusintha nyengo kukana.