Ubuchwepheshe |Yiziphi Izinto ezihlobene Nezakhiwo ze-Polyurethane Flexible Foam

Kungani kunezinhlobo eziningi kangaka zamagwebu e-polyurethane aguquguqukayo kanye nezicelo eziningi kangaka?Lokhu kungenxa yezinhlobonhlobo zezinto zokukhiqiza zokukhiqiza, ukuze izakhiwo ze-flexible polyurethane foams ezenziwe nazo zihluke.Bese, izinto zokusetshenziswa ezisetshenziselwa amagwebu e-polyurethane aguquguqukayo Imvelo yomkhiqizo oqediwe inamuphi umphumela?

1. I-polyether polyol

Njengomsebenzi oyinhloko wokukhiqiza igwebu le-polyurethane eliguquguqukayo, i-polyether polyol ihlangana ne-isocyanate yakhe i-urethane, okuwukusabela kwamathambo emikhiqizo yegwebu.Uma inani le-polyether polyol lenyuka, inani lezinye izinto zokusetshenziswa (isocyanate, amanzi kanye ne-catalyst, njll.) liyancishiswa, okulula ukubangela ukuqhekeka noma ukuwa kwemikhiqizo ye-foam eguquguqukayo ye-polyurethane.Uma inani le-polyether polyol liyancipha, umkhiqizo we-polyurethane we-foam oguquguqukayo otholakalayo uzoba nzima futhi ukuqina kuzoncishiswa, futhi umuzwa wesandla uyoba mubi.

2. I-ejenti ekhipha amagwebu

Ngokuvamile, amanzi kuphela (ikhemikhali egwebungula i-ejenti) asetshenziswa njenge-ejenti ekhihliza ugwebu lapho kwakhiwa amabhulokhi e-polyurethane anomthamo omkhulu kuno-21g/cm3, futhi amaphuzu aphansi abilayo njenge-methylene chloride (MC) asetshenziswa ekwakhiweni kokuminyana okuphansi noma i-ultra. -ukwakheka okuthambile.Amakhomidi (ama-ejenti afuthayo ngokomzimba) asebenza njengama-axiliary blowing agents.

Njenge-ejenti evuthelayo, amanzi ahlangana ne-isocyanate akhe amabhondi e-urea futhi akhulule inani elikhulu le-CO2 nokushisa.Lokhu kusabela kungukusabela kwesandiso seketango.Lapho amanzi engeziwe, i-foam iyancipha futhi iqina kakhulu.Ngesikhathi esifanayo, izinsika zamaseli ziba zincane futhi zibe buthakathaka, okunciphisa amandla okuthwala, futhi zijwayele ukuwa nokuqhekeka.Ngaphezu kwalokho, ukusetshenziswa kwe-isocyanate kuyanda, futhi ukukhululwa kokushisa kuyanda.Kulula ukubangela ukushiswa komnyombo.Uma inani lamanzi lidlula izingxenye ezi-5.0, i-ejenti ekhihliza amagwebu kufanele yengezwe ukuze imunce ingxenye yokushisa futhi igweme ukushiswa okuphakathi.Lapho inani lamanzi lincishiswa, inani le-catalyst liyancishiswa ngokufanayo, kodwa ukuminyana kwegwebu le-polyurethane elitholakala kalula liyakhula.

isithombe

I-axiliary blowing ejenti izonciphisa ukuminyana nobulukhuni begwebu eliguquguqukayo le-polyurethane.Njengoba i-ejenti yokuphefumula eyisiza ithatha ingxenye yokushisa okusabelayo ngesikhathi sokufakwa kwe-gasification, izinga lokuphulukisa liyancipha, ngakho-ke kuyadingeka ukwandisa ngokufanele inani le-catalyst;ngesikhathi esifanayo, ngenxa yokuthi i-gasification ibamba ingxenye yokushisa, ingozi yokushiswa okuyisisekelo iyagwenywa.

3. I-Toluene disocyanate

Igwebu le-polyurethane eliguquguqukayo ngokuvamile likhetha i-T80, okungukuthi, ingxube yama-isomer amabili we-2,4-TDI kanye ne-2,6-TDI enesilinganiso (80±2)% kanye (20±2)%.

Lapho inkomba ye-isocyanate iphakeme kakhulu, indawo engaphezulu izonamathela isikhathi eside, i-modulus yokucindezela yomzimba wegwebu izokhula, isakhiwo senethiwekhi ye-foam sizoba sikhulu, iseli elivaliwe lizokhula, izinga lokuphindaphinda lizokwehla, futhi ngezinye izikhathi. umkhiqizo uzoqhekeka.

Uma inkomba ye-isocyanate iphansi kakhulu, amandla omshini kanye nokuqina kwe-foam kuzoncishiswa, ukuze i-foam ijwayele ukuqhekeka okuhle, okuzogcina kubangele inkinga yokuphindaphinda okubi kwenqubo ye-foaming;ngaphezu kwalokho, uma inkomba ye-isocyanate iphansi kakhulu, izokwenza futhi isethi yokucindezelwa kwegwebu le-polyurethane libe likhudlwana, futhi ingaphezulu legwebu livame ukuzwa limanzi.

4. I-Catalyst

1. I-tertiary amine catalyst: I-A33 (isixazululo se-triethylenediamine esinengxenye enkulu engu-33%) isetshenziswa ngokujwayelekile, futhi umsebenzi wayo ukukhuthaza ukusabela kwe-isocyanate namanzi, ukulungisa ukuminyana kwegwebu kanye nezinga lokuvulwa kwebhamuza, njll. ., ikakhulukazi ukukhuthaza ukusabela okukhihliza amagwebu.

Uma inani le-tertiary amine catalyst liningi kakhulu, lizokwenza ukuthi imikhiqizo ye-polyurethane foam ihlukane, futhi kuzoba nama-pores noma ama-bubbles ku-foam;uma inani le-tertiary amine catalyst lincane kakhulu, igwebu le-polyurethane eliwumphumela lizoncipha, amaseli avaliwe, futhi lizokwenza umkhiqizo wegwebu ube ugqinsile.

2. I-Organometallic catalyst: I-T-9 ngokuvamile isetshenziswa njenge-organotin octoate catalyst;I-T-9 iyisisusa sokusabela kwejeli esinomsebenzi ophezulu we-catalytic, futhi umsebenzi wayo oyinhloko ukukhuthaza ukusabela kwejeli, okungukuthi, ukusabela kamuva.

Uma inani le-organotin catalyst lenyuswa ngokufanelekile, kungatholakala igwebu elihle le-polyurethane yeseli evulekile.Ukwandisa ngokuqhubekayo inani le-organotin catalyst kuzokwenza igwebu liqine kancane kancane, okuholela ekunciphiseni namaseli avaliwe.

Ukunciphisa inani le-tertiary amine catalyst noma ukwandisa inani le-organotin catalyst kungakhuphula amandla odonga lwefilimu yebhamuza le-polymer lapho kukhiqizwa igesi enkulu, ngaleyo ndlela kuncishiswe isenzakalo sokubhoboza noma ukuqhekeka.

Ukuthi igwebu le-polyurethane linesakhiwo esikahle seseli elivulekile noma elivaliwe ikakhulukazi kuncike ekutheni isivinini sokusabela kwejeli kanye nesivinini sokunwetshwa kwegesi kuyalingana ngesikhathi sokwakheka kwegwebu le-polyurethane.Le bhalansi ingafinyelelwa ngokulungisa uhlobo nenani le-tertiary amine catalyst catalysis kanye nokuqiniswa kwegwebu kanye namanye ama-agent asizayo ekwakhiweni.

Isimemezelo:Isihloko sicashunwe kusohttps://mp.weixin.qq.com/s/JYKOaDmRNAXZEr1mO5rrPQ (isixhumanisi sinamathiselwe).Ukuxhumana nokufunda kuphela, ungenzi ezinye izinjongo zezohwebo, akumele imibono nemibono yenkampani, uma udinga ukuphrinta kabusha, sicela uxhumane nomlobi wokuqala, uma kukhona ukwephulwa, sicela usithinte ngokushesha ukuze wenze ukucubungula ukususa.