La macandelo alandelayo achaza ukuguquka kwe-viscoelastic kwe-polyurethane foam inqanaba ngenqanaba, edibanisa iindlela zokusabela, izinto ezibonakalayo, kunye nezinto ezinokwenziwa ukuze kuvele imveliso.

1. Iingcamango eziSiseko

1. Ukuxinana

Ukuxinana kumela ukuxhathisa kwezinto ukuba zihambe kwaye kubonisa indlela eziziphatha ngayo. Ukuxinana okuphezulu kuthetha ukuxinana okuphantsi.

2. Ukuqina

Ukuthamba kubhekisa kubuchule bezinto zokubuyisela imo yazo yokuqala emva kokuguquka. Ukuthamba okukhulu kunika ukumelana okungcono nokuguquka kunye nokuwa kwefoam.

3. Inqaku leGel

Inqaku lejeli lutshintsho olubalulekileyo apho inkqubo itshintsha ukusuka kulwelo oluhambayo ukuya kwinethiwekhi eqinileyo engahambiyo. Lelona nqanaba libalulekileyo lokwahlulahlula kwinkqubo yokwenza amagwebu.

4. Intsingiselo iyonke

Ngexesha lonke lokwenziwa kwegwebu, i-viscosity iyanda rhoqo, ngelixa i-elasticity ikhula kancinci kancinci ukusuka ekubeni buthathaka kakhulu ukuya ekubeni namandla. Emva kokufakwa kwe-gelation, i-elasticity iba luphawu olulawulayo lwenkqubo.

2. Uphuhliso lweViscoelastic ngeSigaba sokuFoaming

Inqanaba loku-1: Inqanaba lokuQala lokuXuba (Ixesha lokuQalisa ngaphambi kwexesha leKrimu)

Iphondo

I-Polyol, i-isocyanate, kunye nezongezo zisandula ukuxutywa. Iimpendulo zeekhemikhali ziqhubeka kancinci, ukuveliswa kwegesi kuncinci, kwaye inkqubo ihlala ilulwelo olufanayo.

Iimpawu zeViscoelastic

• I-viscosity ephantsi kunye nokuhamba kakuhle kakhulu.
• Akukho kuqina komzimba.
• Phantsi kwamandla angaphandle, izinto zihamba ngokukhululekileyo kwaye ukuguquka kwazo akunakulungiseka.

Unobangela woTshintsho

Iitsheyini zemolekyuli azikayikhi ii-crosslink ezibalulekileyo. Izinga lokusabela le-NCO-OH lisephantsi, kwaye akukho nethiwekhi ye-polymer esekwe.

Ukujongwa kweMveliso

Umxube ubonakala ucacile okanye ufana nobisi kancinci kwaye uphuma ngokukhululekileyo.

Inqanaba lesi-2: Inqanaba lekhrimu (Ukuqaliswa kokuGweba)

Iphondo

Amanqanaba okusabela ayakhawuleza. Amanzi asabela nge-isocyanate ukuze avelise ubungakanani obukhulu be-CO₂. Inkqubo ijika ibe mhlophe, kuvela amaqamza amancinci, kwaye kuqala ukwanda.

Iimpawu zeViscoelastic

• Ukuqina kwe-viscosity kukhula ngokukhawuleza njengoko ii-oligomers kunye nee-molecular chains ezinde zisenzeka.
• Ukuqina okubuthathaka kuqala ukubonakala ngenxa yokwakheka kwemibutho ye-preliminary chain.
• Inkqubo ihlala iqinile kakhulu kwaye iyaqhubeka nokuhamba nokunwebeka.

Uphawu oluPhambili

Amaqamza ahlala ebumbeka kwaye ekhula. Le nkqubo ixhomekeke kakhulu kwi-viscosity yayo ukuze igqume amaqamza egesi kwaye ithintele ukuphuma kwegesi.

Inqanaba lesi-3: Inqanaba lokunyuka (Ixesha lokuGweba ngokuNzulu Ngaphambi koKukhula)

Iphondo

Amanqanaba okusabela afikelela kwincopho yawo. Igesi eninzi iveliswa, umthamo wegwebu uyanda ngokukhawuleza, kwaye iiseli zikhula ngokukhawuleza. Eli lelona nqanaba libalulekileyo lokwenziwa kwegwebu.

Iimpawu zeViscoelastic

• Ukuqina kuyaqhubeka nokwanda ngokukhawuleza.
• Ukuhamba kwamanzi kuncipha kakhulu.
• Iimpendulo ezidibanisayo ziyanda, nto leyo ebangela ukuba ukuthamba kwande ngokukhawuleza.
• Ukuziphatha kwe-Viscoelastic kuya kucaca ngakumbi, ngokuthe ngcembe kutshintshela ekubeni kulawuleke ngakumbi.
• Le nto iphuhlisa amandla okuxinana kunye nokumelana nokuwa.

Xa yoluliwe, igwebu liyajikajika kodwa liyabuya kancinci xa amandla esusiwe. Amaqamza akhulayo ahlala ezinzile ngokufanelekileyo ngaphakathi kwi-matrix.

Iziphumo zeNkqubo

• Ukuba ukuthamba akwanelanga kwaye i-viscosity iphezulu, amaqamza anokuqhekeka, ahlangane, okanye awe.
• Ukuba ukuthamba kwenzeka kwangethuba kakhulu okanye ngamandla kakhulu, ukwandiswa kwefoam kuyathintelwa, nto leyo ebangela ukuba kubekho uxinano olukhulu lokugqibela.

Inqanaba lesi-4: I-Gel Point (Inqanaba loTshintsho oluBalulekileyo)

Iphondo

Inethiwekhi edibeneyo enamacala amathathu imiselwe ngokusisiseko. Ukugqwala kunye nokufakwa kwegwebu kufikelela kwibhalansi, nto leyo eyenza oku kube yeyona ngongoma ibalulekileyo kuyo yonke inkqubo.

Utshintsho lweViscoelastic

• Inkqubo ilahlekelwa ngamandla ayo okuhamba.
• Ukubonakala ngathi yi-viscosity kusondela kwi-infinity.
• Ukuthamba kuba yimpawu ephambili.
• Ukuguquka kwesikhumba kuba lula kakhulu, kwaye emva kokucinezelwa okanye ukolulwa kwesikhumba, umzimba uyaphola ngokukhawuleza.
• Izakhiwo zeeseli ziyazinza ngokusisigxina njengoko iindonga zeeseli ziqina.

Ukubaluleka kweMveliso

• Ukwanda kwe-gelation kwenzeka kwangethuba kakhulu kunokukhokelela ekukhuleni okungaphelelanga kunye noxinano oluphezulu lwe-foam.
• Ukunyuka kwegesi okwenzeka emva kwexesha kunokubangela ukulahleka kwegesi, ukushwabana kwefoam, kunye nokuwa.

Inqanaba lesi-5: Inqanaba lokuPhila kunye noKukhula (Emva koKukhuliswa)

Iphondo

Amaqela aseleyo asabelayo ayaqhubeka nokusabela, omeleza ngakumbi inethiwekhi edibeneyo. Ukwandiswa kwefoam kuyaphela, kwaye izinto ziyaqina kancinci kancinci.

Iimpawu zeViscoelastic

• Uxinano lwe-Crosslink luyaqhubeka nokwanda.
• Ukuqina kunyuka kancinci kancinci.
• Ukuthamba kuyazinza.

Kwifoam eguquguqukayo:

• Ukuqina okuphezulu kuyagcinwa.
• Ukuqina nokuqina okuhle kuyagcinwa.

Kwifoam eqinileyo:

• Ukuthamba kuyancipha.
• Izinto ezisetyenziswayo ziyaguquka ziye kwimeko eqinileyo neqinileyo.
• Ukuguquka kwesakhiwo kuba yiplastiki ngakumbi kunokuba kube yilastiki.

Uxinzelelo lwangaphakathi oluseleyo luqala ukubakho kodwa lukhutshwa kancinci kancinci ngexesha lokunyanga, nto leyo evumela iipropati ze-viscoelastic ukuba zihlale zizinzile.

Utshintsho olulandelayo

Emva kokunyangwa ngokwaneleyo kwiimeko ezingqongileyo, ukudibana kweentambo kuba yinto epheleleyo, kwaye iipropati zoomatshini kunye ne-viscoelastic zihlala zizinzile.

3. Izinto eziphambili ezichaphazela ukuziphatha kwe-Viscoelastic

1. IiCatalysts (Eyona nto ibalulekileyo yoLawulo)

IiCatalysts ezivuthelayo

• Ukukhawulezisa ukuveliswa kwegesi.
• Khuthaza uphuhliso lwe-viscosity lwakwangoko.
• Yenza ukwandiswa kwefoam kuqhubeke ngokukhawuleza.

Iikhatalyst zeGel

• Khawulezisa ii-crosslinking reactions.
• Seka inethiwekhi ye-elastiki ngokukhawuleza.
• Nciphisa ixesha lejeli.

Ukungalingani kweCatalyst

Ukulinganisela okungalunganga phakathi kokuvuthela kunye nee-catalysts zejeli kuphazamisa ukuhambelana kwe-foaming-gelation, kuphazamisa iprofayili ye-viscoelastic, kwaye kunokubangela ukudilika kwe-foam, ukushwabana, okanye izakhiwo zeeseli ezirhabaxa.

2. Ubushushu bezinto eziluhlaza

Ubushushu obuphezulu

• Ikhawulezisa amazinga okusabela ngokubanzi.
• Ukwandisa amazinga ophuhliso lwe-viscosity kunye ne-elasticity.
• Ibangela ukwakheka kwe-gel kwangaphambili.

Ubushushu obuphantsi

• Inciphisa izinga lokuphendula.
• Ivelisa ukunyuka okuthe ngcembe kweempawu ze-viscoelastic.
• Ilibazisa ukwakheka kwegesi kwaye yandisa umngcipheko wokulahleka kwegesi.

3. Isalathisi se-NCO (Isalathisi se-Isocyanate)

Isalathiso se-NCO esiPhakamileyo

• Ikhuthaza ukunxibelelana okuqinileyo.
• Iyandisa ukuthamba kunye nokuqina ngokukhawuleza.
• Ivelisa igwebu elibuthathaka ngakumbi.

Isalathisi se-NCO esiphantsi

• Iziphumo zokungabikho konxibelelwano olwaneleyo.
• Kukhokelela ekuthambekeni okubuthathaka kunye ne-viscosity ephezulu eseleyo.
• Ivelisa igwebu elithambileyo elinokuguquguquka okukhulu kwaye lilulame kakuhle.

4. Ii-Surfactants kunye neeFillers

Izinto ezibangela ukudumba kweSilicone

• Phucula ulawulo loxinzelelo lwe-interfacial.
• Khuthaza ukusasazwa okufanayo kwe-viscoelastic kuyo yonke i-foam.
• Thintela izakhiwo zeeseli ezingalinganiyo ezibangelwa kukungafani kwe-viscosity okanye ukuthamba kwazo.

Izizalisi ezingaphiliyo

• Yandisa i-viscosity yokuqala kwenkqubo.
• Yehlisa ukuthamba.
• Yenza isakhiwo sefoam sibe siqinile xa sisonke.

5. Ulwakhiwo lwePolyol

IiPolyols eziSebenza ngokuPhezulu

• Yenza iinethiwekhi ezidityanisiweyo ngokulula.
• Yandisa ukuthamba kunye nokuqina ngokukhawuleza.

IiPolyols ezineeMolekyuli eziPhakamileyo, ezineeTshayini ezinde

• Velisa inkqubo yokudibanisa ngokuthe ngcembe.
• Yenza indlela ethambileyo yokuthamba.
• Gcina i-viscosity ixesha elide.
• Ziyimpawu ze-formulations ze-foam eziguquguqukayo.

4. Isishwankathelo: I-Trend ye-Viscoelastic iyonke ngexesha lokuGxobhoza

Ngokwenyani, yonke inkqubo yokukhupha amagwebu yinguqu ye-rheological apho inkqubo iguquka ukusuka kwi-aulwelo oluqinileyo kuphelakwiinethiwekhi ye-elastomeric edibeneyo enamacala amathathu.

Ibhalansi phakathiukwandiswa kwefoam kunye nokususwa kwe-gelating, njengoko kubonakaliswa ziimpawu ezitshintshayo ze-viscoelastic zenkqubo, imisela ngokuthe ngqo ulwakhiwo lokugqibela lwefoam, uzinzo olulinganayo, kunye nomgangatho wemveliso iyonke.