dhow
Dooro Boggaga
Caalamka
Baraha Bulshada
Aragtida: 255 Qore: Shengda Waqtiga Daabacaadda: 2026-07-16 Asal ahaan: Goobta
Tusmada Tusmada
● Maxaa ka dhigaya buundooyinka HPMC ka duwan yihiin?
● Cabbirrada Muhiimka ah ee Fasallada HPMC
>> Heerarka Viscosity (LV, MV, HV)
● Codsiga-Qaar ka ah buundooyinka HPMC
>> Heerka dhismaha-HPMC (Hoobiyeyaasha, Xabagta Tile, EIFS)
>> Daawada-Fasalka HPMC (E, K Taxanaha)
>> Heerka Cuntada HPMC (Qoraalka iyo Deganaanshaha)
>> Saabuunta-Grade iyo PVC-Grade HPMC
● Sida Loo Doorto Heerarka saxda ah ee HPMC
● Isbeddellada Wershadaha iyo Aragtida Khubarada ee Heerarka HPMC
● Talooyin wax ka qabashada wax ku ool ah ee HPMC ee Soo saarista
● Waa maxay sababta ay ula shuraakoobeen soosaaraha HPMC ee xirfada leh
● FAQs
Hydroxypropyl methylcellulose ( HPMC ) ma aha oo kaliya dhumuc guud; darajooyin kala duwan ayaa bixiya waxqabad aad u kala duwan oo ku saabsan xabagta tile, plasters gypsum, saabuunta, shaambooyinka, iyo hababka cuntada, markaa doorashada heerka saxda ah ayaa muhiim u ah soosaarayaasha iyo iibsadayaasha. [wotaichem ]
Sida a Soo saaraha ether-ka cellulose ee ka shaqeeya dhismaha caalamiga ah iyo noocyada kiimikaad ee maalinlaha ah, waxaan arkay sida isbeddelka yar ee darajada HPMC uu u rogi karo qaabaynta xadka mid deggan, sahlan - in la codsado, badeecad qaali ah. Heerarka HPMC waxaa ugu horrayn lagu kala soocaa miisaanka , molecular , iyo qaabka beddelka (E, K, F series), kuwaas oo si wada jir ah u xakameeya sii-haynta biyaha, shaqaynta, samaynta filimada, iyo habdhaqanka sii deynta. [kimacellulose ]
Biyaha qabow, HPMC waxay ku kala firdhisaa si ay u samayso xalal cad ama waxoogaa daruuro leh ama jeel ah, oo u dhaqmaya sidii dhumuc aan-ionic ahayn, dhirtu ka soo baxday, xasiliye, binder, iyo polymer-samaynta filimada guud ahaan dhismaha, dawooyinka, cuntada, saabuunta, iyo daryeelka shakhsi ahaaneed. Sababtoo ah guud ahaan waxaa loo arkaa inay tahay mid badbaado leh oo la jaan qaadi karta sibidhka, gypsum, surfactants, iyo walxo badan oo firfircoon, HPMC waxay noqotay wax lagu daro laf dhabarta oo loogu talagalay agabka dhismaha ee waxqabadka sareeyo iyo alaabada kiimikaad ee maalinlaha ah. [unilongindustry ]
Ficil ahaan, naqshadeeyayaasha waxay u kala saaraan HPMC hoose , dhexdhexaad , iyo noocyo viscosity sare ah , oo caadi ahaan lagu cabbiro mPa·s si loo helo xal caadi ah. [wotaichem ]
Viscosity hoose (LV): qiyaastii 5-100 mPa·s, oo leh milmi degdeg ah iyo dhumuc yar, oo ku habboon nidaamyada la buufin karo iyo dahaadhka kiniinka. [youtube ]
Viscosity dhexdhexaad ah (MV): qiyaastii 400-5,000 mPa·s, dheellitirka dhumucda iyo qulqulka, oo ku badan hoobiyeyaal iyo koollo badan. [wotaichem ]
Viscosity Sare (HV): qiyaastii 20,000-200,000 mPa·s, oo keenaysa sii-hayn adag oo biyo ah iyo xoog jel oo loogu talagalay koollada tile, balastarrada, iyo kiniinnada-sii daynta la xakameeyey. [kimacellulose ]
Kala duwanaanshahan ayaa ka muuqda darajooyinka dhismaha ganacsiga sida MP400, MP60M, MP100M, MP150M, MP200M , kuwaas oo kor u qaadaya viscosity iyo biyo haynta nidaamka sibidhka ku salaysan ee sii kordhaya. [kimacellulose ]
Dhismuhu waa mid ka mid ah macaamiisha ugu weyn ee HPMC , gaar ahaan sibidhka iyo gypsum-ka alaabta qallalan. Darajooyinka dhismaha caadiga ah waxaa loogu talagalay daaqada viscosity ee qiyaas ahaan 400-200,000 mPa·s si loo habeeyo wakhtiga furan, haynta biyaha, iyo dareemida tuujinta. [wotaichem ]
Darajooyinka dhismaha ee wakiilka iyo viscosity (2% xal): [kimacellulose ]
| Fasalka (Dhismaha) diiradda | viscosity NDJ (mPa·s, 2%) | Brookfield viscosity (mPa·s, 2%) | isticmaalka caadiga ah |
|---|---|---|---|
| HPMC MP400 | 320-480 (kimacellulose ) | 320-480 (kimacellulose ) | Hoobiyeyaasha heerka gelitaanka, haysashada aasaasiga ah ee biyaha |
| HPMC MP60M | 48,000-72,000 (kimacellulose ) | 24,000-36,000 (kimacellulose ) | Xabagta tile, wakhtiga furan oo la hagaajiyay |
| HPMC MP100M | 80,000-120,000 (kimacellulose ) | 40,000-55,000 (kimacellulose ) | Waxqabadka sare ee xabagta tile, putty |
| HPMC MP150M | 120,000-180,000 (kimacellulose ) | 55,000-65,000 (kimacellulose ) | EIFS jaakadaha saldhigga ah, hoobiyeyaal toosan |
| HPMC MP200M | 180,000-240,000 (kimacellulose ) | 70,000-80,000 (kimacellulose ) | Malaastayaal culus oo kulul, cimilo qalalan |
Wax ku biirinta waxqabadka muhiimka ah ee dhismaha: [wotaichem ]
- Ku haysashada biyaha ee sibidhka iyo nidaamyada gypsum si loo hubiyo fuuq-celinta saxda ah oo looga fogaado qalajinta hore.
-Shaqo la xoojiyey iyo rheology , taasoo ka dhigaysa hoobiye si fudud in la isku daro, faafin, iyo tuman.
-Adhesion xoog badan iyo caabbinta sag , gaar ahaan rakibaadda dhoobada toosan.
- Iska caabbinta dildilaaca oo la hagaajiyay iyo adkeysiga iyada oo loo marayo isku xirnaanta wanaagsan iyo buuxinta dabacsanaan ee daldaloolada.
Soosaarayaasha casriga ahi waxay inta badan isbarbardhigaan viscosity-ga nooca badeecada-tusaale, 20,000–60,000 mPa·s ee xabagta tile C1/C2, 20,000–40,000 mPa·s ee gidaarka, iyo 60,000–150,000 mPa·s ee EIFS adhesives. [wotaichem ]
HPMC-da dawooyinka waxa lagu habeeyey koodka hypromellose waxaana loo isticmaalaa sidii xidhe, filim-hore, iyo matrix-sii dayn la xakameeyey oo ah foomamka qiyaasta qiyaasta afka iyo ka joojinta dareeraha ah. [kimacellulose ]
Darajooyinka farmasiga ee wakiilka iyo viscosity: [pubmed.ncbi.nlm.nih ]
| Fasalka (Pharma) | Viscosity (cps / mPa·s) | Nooca beddelka | Hawlaha ugu muhiimsan |
|---|---|---|---|
| HPMC E5 | 4.0-6.0 (kimacellulose ) | Hypromellose 2910 | Dahaarka filimka hoose ee viscosity, xalalka |
| HPMC E6 | 4.8–7.2 (kimacellulose ) | Hypromellose 2910 | Si la mid ah E5, viscosity wax yar ka sarreeya |
| HPMC E15 | 12.0-18.0 (kimacellulose ) | Hypromellose 2910 | Kiniinnada Matrixka oo leh indho-beel dhexdhexaad ah |
| HPMC E4M | 3,200–4,800 (kimacellulose ) | Hypromellose 2910 | Filimkii hore ee viscosity-ka sare, matrices jel |
| HPMC F50 | 40-60 (kimacellulose ) | Hypromellose 2906 | Filim-samaynta dahaarka iyo xabagta |
| HPMC K100 | 80-120 (kimacellulose ) | Hypromellose 2208 | Viscosity dhise, xidhe |
| HPMC K4M | 3,200–4,800 (kimacellulose ) | Hypromellose 2208 | Matrix-sii-daynta la xakameeyey, jel xoog leh (wotaichem ) |
| HPMC K100M | 80,000-120,000 (kimacellulose ) | Hypromellose 2208 | Kiniinada si tartiib tartiib ah loo sii daayo, xoog jel oo sarreeya (wotaichem ) |
Nidaamyada daahan kiniiniga ah ee la kantaroolay, darajooyinka viscosity-ka sare sida K4M, K15M, K100M waxay dhisaan matries hydrophilic cufan oo kordhiya wakhtiga daahista iyo sii deynta daroogada, halka darajooyinka hoose sida E5, E6 ay taageerayaan daahaarka siideynta degdega ah. [meskajoinway ]
Heerka cuntada HPMC, oo inta badan lagu calaamadiyo E464 , waxa loo isticmaalaa sidii dhumuc, xasiliye, emulsifier, iyo filim hore u ahaa cuntooyinka iyo cabitaannada warshadaysan. [unilongindustry ]
Heerarka cuntada caadiga ah iyo viscosity :kimacellulose ]
| Fasalka (Cuntada) | Viscosity (cps) | hadalka calaamadda |
|---|---|---|
| HPMC E5 FG | 4.0-6.0 | Hypromellose E464kimacellulose ) |
| HPMC E6 FG | 4.8–7.2 | Hypromellose E464kimacellulose ) |
| HPMC E15 FG | 12.0-18.0 | Hypromellose E464kimacellulose ) |
| HPMC E4M FG | 3,200-4,800 | Hypromellose E464kimacellulose ) |
| HPMC F50 FG | 40-60 | Hypromellose E464kimacellulose ) |
| HPMC K100 FG | 80-120 | Hypromellose E464kimacellulose ) |
| HPMC K4M FG | 3,200-4,800 | Hypromellose E464kimacellulose ) |
| HPMC K100M FG | 80,000-120,000 | Hypromellose E464kimacellulose ) |
Soosaarayaasha cuntada waxay u isticmaalaan darajooyinkan: [unilongindustry ]
- Ku dhis viscosity iyo dareenka afka suugada, dhaymada, iyo analooga caanaha.
U shaqee sidii beddelayaal baruur ah , oo soo saara dheeman kareem leh oo ku jira badeecooyinka dufanku ku yar yahay.
- Kor u qaad haynta biyaha ee alaabta roodhida iyo cajiinka aan lahayn gluten-free si loo yareeyo qallaylka.
- Samee filimaan dusha ilaalinaya oo taageera nolosha shelf iyo muuqaalka.
Qalabka saabuunta ee HPMC waxaa loogu talagalay dhar-dhaqidda iyo alaabta nadiifinta , halkaas oo ay dejiso qaabaynta oo ay hakiso walxaha. [kimacellulose ]
Darajooyinka saabuunta :kimacellulose ]
| Fasalka ( saabuunta) | NDJ viscosity (mPa·s, 2%) | Brookfield viscosity (mPa·s, 2%) | Isticmaal feejignaan |
|---|---|---|---|
| HPMC MP100MS | 80,000-120,000 | 40,000-55,000 (kimacellulose ) | Dhumucda, ka joojinta, xasiloonida |
| HPMC MP150MS | 120,000-180,000 | 55,000-65,000 (kimacellulose ) | Saabuunta dareeraha ah ee viscosity-sare |
| HPMC MP200MS | 180,000-240,000 | 70,000-80,000 (kimacellulose ) | Saabuunta shaqada culus, socodka la xakameeyey |
Darajooyinkani waxay wanaajiyaan viscosity, xasiloonida wajiga, joojinta walxaha, iyo sifooyinka socodka dareeraha iyo budada labadaba, waxayna la jaan qaadayaan kuwa wax dhisa ee caadiga ah. [unilongindustry ]
Heerka PVC-HPMC (Hydrocel HPMC) wuxuu u shaqeeyaa sidii gargaar farsameyn iyo xasiliye xeryahooda PVC, hagaajinta qulqulka dhalaalka, iska caabbinta saameynta, iyo kuleylka/UV xasilloonida. Darajooyinka wakiillada waxaa ka mid ah E50, F50, K100 oo leh viscosity agagaarka 40-120 cps ee codsiyada caadiga ah ee PVC. [kimacellulose ]
Marka loo eego qaabeeyaha wax ku oolka ah, doorashada darajada HPMC waa inay raacdaa hab-socod shaqo oo xul ah oo lix tallaabo ah , halkii diiradda la saari lahaa kaliya qiimaha ama aqoonta. [wotaichem ]
1. Qeex codsiga iyo bartilmaameedyada waxqabadka.
Dhismaha: waqti furan, iska caabin simbiriirixan, karti shaqo, xoog. [wotaichem ]
Daawooyinka: astaanta siideynta, adkeysigga kiniinka, tayada dahaarka. [pubmed.ncbi.nlm.nih ]
Cuntada/ saabuunta/daryeelka gaarka ah: hufnaanta, hufnaanta, xasilloonida, iyo habaynta. [unilongindustry ]
2. Dooro band viscosity (LV, MV, HV).
Ka bilow inta udhaxaysa viscosity ee caadiga ah ee loo isticmaalo qaybta alaabtaada, ka dibna isku hagaaji qaybaha tijaabada ka dib. [wotaichem ]
3. Dooro taxanaha beddelka (E, K, F).
U isticmaal taxane-K si aad u hesho maaddooyinka jel ee xooggan iyo sii-deynta joogtada ah, Taxanaha E- qaabaynta filimada-samaynta iyo dhismaha matrixka, iyo taxanaha F-daahan waxqabadka sare leh iyo codsiyada filimada. [kimacellulose ]
4. Isku hagaaji darajada cimilada iyo qalabka.
Deegaan kulul, qalalan ayaa inta badan u baahan viscosity sare si uu biyaha ugu ceshado hoobiyeyaal; xaaladaha qaboojiyaha ama qoyaanka badan ayaa ka faa'iidaysan kara mawjadaha wax yar ka hooseeya si looga fogaado dhumucda xad-dhaafka ah. Hubi xawaarahaaga isku dhafka ah, heerkulka biyaha, iyo pH si aad uga fogaato barar iyo luminta viscosity. [wotaichem ]
5. Samee tijaabooyinka shaybaadhka iyo goobta.
Qiimee viscosity, socodka, caabbinta sag, adhesion, iyo habdhaqanka dildilaaca ee dhismaha; kala diri, profile siideynta , iyo tayada filimka ee farmashiyaha; qaabka iyo xasiloonida cuntada iyo saabuunta. [pubmed.ncbi.nlm.nih ]
6. Kor u qaad qiyaasta oo ku dar waxyaallaha wax lagu daro.
Ku dar HPMC iyo ethers istaarijka ah, budada dib loo cusboonaysiin karo, maaddooyinka hawada soo geliya, balaastikada, ama qalabyada korka si loo hagaajiyo waxqabadka iyo qiimaha. [unilongindustry ]
Soo-saare ahaan, Shandong Shengda New Material Co., Ltd. waxay ku taageertaa habkan hagitaan farsamo-gaar ah oo arji ah, muuqaalada viscosity ee ku habboon, iyo sahayda muddada-dheer ee xasilloon ee guud ahaan dhismaha, daryeelka shakhsi ahaaneed, iyo warshadaha kale. [wotaichem ]
Falanqaynta suuqa dhow waxay muujineysaa kobaca joogtada ah ee baahida caalamiga ah ee HPMC, oo ay wadaan kaabayaasha iyo horumarinta hantida ma-guurtada, dawooyinka sii-deynta joogtada ah, iyo alaabada daryeelka shaqsiyeed ee ku saleysan dhirta. Isla mar ahaantaana, qaabeeyayaasha ayaa u dhaqaaqaya dhanka darajooyinka HPMC ee takhasuska leh oo leh muuqaal la hagaajiyay iyo muuqaalada beddelka xabagta tile ee horumarsan, isku dhisyada is-heeraynta, iyo nidaamyada EIFS. [unilongindustry ]
Sida qof si dhow ula shaqeeya kooxaha R&D, waxaan arkaa saddex isbeddel oo wax ku ool ah oo qaabaynaya xulashada fasalka:
- Dhisidda cagaarka iyo adkeysiga: Heerarka dhismaha ee viscosity-sare ee wanaajiya xajinta biyaha iyo iska caabbinta dildilaaca ayaa si isa soo taraysa loogu door bidaa nidaamyada hoobiye ee waara. [wotaichem ]
- Nadiifinta-calaamad-qaadayaasha: Noocyada dawooyinka iyo daryeelka-shaqsiyeedka waxay ku tiirsan yihiin HPMC sidii aan-ionic, cellulose-ka-soo-saar polymer polymer ah oo ku habboon summada nadiifka ah iyo meelaynta dhirta ku salaysan. [pharcos.co ]
- Kalsooni habaysan: OEM/ODM shuraakada waxay inta badan dalbadaan isku darka HPMC caadadii ee u dhigma bamgareynta gaarka ah, buufinta, iyo dabeecadaha dhamaystirka halkii ay ka ahaan lahaayeen noocyada viscosity ee guud. [wotaichem ]
Iibsadayaasha iyo kuwa wax soo saara, la-hawlgalayaasha soo saaraha ether-ka cellulose ee khaaska ah oo bixin kara darajooyinka caadiga ah iyo kuwa la habeeyey labadaba hadda waa faa'iido tartan, kaliya maahan dookh la raadinayo. [kimacellulose ]
Maareynta saxda ah waa lama huraan si loo furo waxqabadka buuxa ee darajada HPMC ee aad dooratay . [wotaichem ]
- Kala firdhi ka hor inta aan la milmin. Ku dar budada si tartiib ah biyo qabow oo xoog leh si aad uga fogaato in ay samaysmaan oo aad hubiso fuuq-bax isku mid ah. [wotaichem ]
- Xakamaynta heerkulka biyaha : laga bilaabo biyaha qabow waxay hagaajinaysaa kala firdhinta; Biyo aad u diiran ayaa abuuri kara jel dusha sare ah wakhti hore. [wotaichem ]
- La soco pH iyo waxa ku jira milixda , taas oo saamayn karta viscosity iyo hufnaanta, gaar ahaan saabuunta iyo ka joojinta afka. [wotaichem ]
- Nidaamyada dhismaha, ku dar HPMC iyo ethers istaarijka ah, RDPs, iyo wakiilada hawada soo gelisa si loo hagaajiyo wakhtiga furan iyo kartida shaqaynta iyada oo aan la kordhinayn viscosity. [wotaichem ]
Faahfaahintan hawl-fulintu inta badan waa faraqa u dhexeeya sheyga u hoggaansan warqadda iyo qaabaynta si fiican uga shaqeysa goobta ama gacanta isticmaalaha. [wotaichem ]
Doorashada darajada saxda ah ee HPMC waa go'aan farsamo oo saameeya waxqabadka, waxtarka kharashka, iyo qanacsanaanta macaamilka ee dhismaha iyo alaabta maalinlaha ah. Soo-saare xirfad leh ether cellulose sida Shandong Shengda New Material Co., Ltd. waxay bixisaa: [wotaichem ]
- Faylal buuxa oo ah heerka-dhismaha, maalin-kiimikaad-kiimikada, iyo darajooyinka kale ee HPMC ee daboolaya kala duwanaanshaha hoose, dhexe, iyo viscosity-ka sare. [wotaichem ]
- Taageero farsamo si loo waafajiyo viscosity iyo profile profiles hoobiyeyaal gaar ah, xabagta tile, saabuunta, ama alaabta daryeelka shakhsi ahaaneed. [wotaichem ]
- Tayo xasiloon iyo sahay , awood u siinaysa joogteynta alaabta muddada-dheer iyo u hoggaansanaanta fudud ee codsiyada xasaasiga ah. [wotaichem ]
Haddii aad cusboonaysiinayso xabagta tile-kaaga, dhejisyada gidaarada, balastarrada gypsum, alaabta nadiifinta, ama qaababka daryeelka shakhsi ahaaneed, la shaqaynta soo saaraha HPMC ee diirada saaraya waxay si weyn u gaabin kartaa wareegyada horumarka waxayna yaraynaysaa kharashaadka tijaabada-iyo-khaladaadka. [kimacellulose ]
Q1: Waa maxay farqiga ugu weyn ee u dhexeeya viscosity hoose iyo sare ee HPMC ee hoobiyeyaal dhismaha?
Viscosity-hooseeya HPMC waxa ay bixisaa milmi degdeg ah iyo dhumuc fudud, halka darajooyinka viscosity-sare ay bixiyaan haynta biyaha oo xoog badan, xoog jel oo sarreeya, iyo iska caabin wanaagsan oo sag-guud ah oo loogu talagalay koollada iyo balastarrada. [kimacellulose ]
Q2: Ma isticmaali karaa hal darajo HPMC ee dhismaha, cuntada, iyo codsiyada daawooyinka?
Aragti ahaan, polymer isku mid ah ayaa ka soo muuqan kara codsiyo kala duwan, laakiin cuntada iyo isticmaalka dawooyinka waxay u baahan yihiin darajooyin u go'ay oo u hoggaansamaya xeerar adag iyo heerarka farmashiyaha, markaa way ka badbaado badan tahay in la isticmaalo darajooyinka HPMC-ga gaarka ah ee warshadaha. [kimacellulose ]
Q3: Sidee bay cimiladu u saamaysaa doorashadayda dhismaha darajada HPMC?
Cimilada kulul, engegan, ama dabaylaha leh waxay caadi ahaan u baahan yihiin viscosity sare HPMC si loo ilaaliyo wakhtiga furan loogana hortago qalajinta hore, halka xaaladaha qaboojiyaha ama qoyaanku ay si fiican u fiicnaan karaan iyada oo leh indho yar yar si looga fogaado hoobiyeyaal adag. [wotaichem ]
Q4: Maxay K4M, E4M, iyo F4M u dhaqmaan si ka duwan haddi ay leeyihiin viscosity la mid ah?
In kasta oo ay wadaagaan viscosity magac ahaan ku dhawaad 4,000 mPa·s, qaab beddelkooda methoxy/hydroxypropyl way kala duwan yihiin, kaas oo beddela heerka fuuq-baxa, qaab-dhismeedka jelka, kulaylka kulaylka, iyo waafaqsanaanta maaddooyinka kale. [wotaichem ]
Q5: Waa maxay meesha ugu fiican marka la dooranayo HPMC ee koollada cusub ee tile?
Qeex bartilmaameedyada waxqabadka (waqtiga furan, iska caabinta silbashada, cimilada), dooro kala duwanaansho dhexdhexaad-ilaa-sare ah, dooro taxane habboon (badanaa E ama F si loo dhiso), ka dibna samee tijaabooyinka shaybaadhka iyo goobta oo leh laba ilaa saddex darajooyin u dhow si loo hagaajiyo rheology iyo dhejinta. [kimacellulose ]
1. Shandong Shengda New Material Co., Ltd. - 'HPMC Fasalada La Sharaxay: Viscosity, Codsiyada iyo Hagaha Xulashada Formulators.' [wotaichem ]
2. Kima Kiimikada - 'Show heerarka kala duwan ee HPMC.'kimacellulose ]
3. Kiimikada Kima - 'Waa maxay darajooyinka kala duwan ee HPMC?' [kimachemical ]
4. Warshadaha Unilong - 'Maxaa Hydroxypropyl Methylcellulose loo isticmaalaa?'unilongindustry ]
5. Cilmi-baarista Istiraatijiyadeed ee Suuqa - 'Hydroxypropyl Methylcellulose Market.'unilongindustry ]
6. PubMed - 'Darajooyinka viscosity ee kala duwan ee HPMC sida wakiilada dahaarka ee habka gudbinta daawada sambabada afka.' [pubmed.ncbi.nlm.nih ]
7. Pharcos - 'Heerarka HPMC iyo Heerarka Viscosity ee Farmashiyaha: Hagaha Buuxa.' [pharcos.co ]
8. MESKA - 'HPMC E3 vs E5 vs E6 ee Codsiyada Dahaarka Filimka.'meskajoinway ]
9. Wotai Kiimikada - 'Jajabka Heerarka ugu dambeeya ee HPMC.'wotaichem ]
10. YouTube - 'Hydroxypropyl Methylcellulose HPMC Derajooyinka iyo Codsiyada.' [youtube ]
