Yam li cas PVA 2488 tuaj yeem rau cov khoom siv los ntawm kev cog lus?

Kev ua cov lus uas zoo thiab kev ua cov lus uas muaj kev nyab xeeb

Yam li cas PVA 2488 88% hydrolysis pab ua cov lus uas zoo, cov lus uas muaj duab, thiab cov lus uas muaj kev nyab xeeb

PVA 2488—ib yam tshuas polyvinyl alcohol uas muaj 88% ntawm hydrolysis—tsim qhov tswv yim zoo tshaj plaws ntawm cov acetate groups uas tsis tau hydrolyzed thiab cov hydrophilic hydroxyl functional groups. Qhov kev ua haujlwm ntawm cov molecules no txhais tau tias nws yuav tsum tau solubilized rau hauv dej ntev, thiab nws kuj pab tsim cov films uas muaj kev zoo tshaj plaws, muaj kev zoo tshaj plaws thiab muaj kev nyab xeeb rau kev siv. Nws muaj molecular weight siab, uas pab tsim cov hydrogen bonding siab thiab cov polymer chains uas sib twb, uas txhais tau tias nws tsis tau crystalline (uas pab tsim kev zoo tshaj plaws ntawm optical clarity) thiab muaj kev nyab xeeb rau kev siv. Thaum siv los tsim cov films, cov polymer chains yuav tsum sau rau ntawm cov surfaces uas tsis muaj qhov tsis zoo, uas yog qhov tseem ceeb rau kev siv los tsim cov coatings lossis cov barrier layers uas tsis muaj lwm yam. Cov films uas tau tsim muaj kev nyab xeeb rau kev tshuaj thiab tsis muaj kev tshuaj rau kev tsim qhov tsis zoo—qhov tseem ceeb rau kev siv hauv packaging, uas muaj kev zoo tshaj plaws thiab kev nyab xeeb rau kev siv.

Daim tshuaj xyuas: PVA 2488-Coated Paperboard rau kev siv hauv packaging rau cov foods uas tsis muaj dej

Qhov tswv yim ntawm qhov khoom siv rau hais cov khoom siv los ntawm lub rooj tsis muaj kev txhawb nqa, lawv siv qhov PVA 2488 uas muaj qhov ntau thiab siv lub rooj khaub ncaws rau lub rooj khaub ncaws uas tsis muaj kev txhawb nqa, thiab qhov no tau pab tshem tawm cov kab laug ntawm lub rooj khaub ncaws, tab sis tsis muaj kev cuam tshuam rau qhov yooj yim ntawm lub rooj khaub ncaws. Hauv qhov kev sim rau kev nyob ntawm lub rooj khaub ncaws rau 38°C thiab 50% RH, cov rooj khaub ncaws uas muaj qhov PVA 2488 tau nyob rau hauv qhov oxygen tsis li 0.1% rau 12 hnub—thiab qhov no tau pab tshem tawm kev sov ntawm cov khoom siv uas muaj lub tshuab thiab cov khoom siv uas muaj lub tshuab. Qhov kev nyob ntawm lub rooj khaub ncaws tau zoo dua 40%, thiab qhov no tau pab tshem tawm kev tshem tawm ntawm cov kab laug rau lub rooj khaub ncaws uas tsis muaj qhov PVA 2488. Tsis tas li ntawd, qhov kev sov ntawm qhov PVA 2488 tau pab tshem tawm cov rooj khaub ncaws rau kev siv dua: qhov no tau nyob ruaj khov rau kev siv thiab kev sib xyaw, tab sis tau tshem tawm ntev rau kev siv lub rooj khaub ncaws. Qhov kev siv no tau pab hais tias PVA 2488 tuaj yeem pab ua lub rooj khaub ncaws uas muaj qhov ntau thiab muaj kev sib xyaw rau kev siv lub rooj khaub ncaws uas muaj kev nyab xeeb thiab muaj kev sib xyaw.

Kev sov ntawm dej uas muaj kev tswj hwm rau kev siv ib zaug uas muaj kev tswj hwm

Kev sov ntawm PVA 2488 uas nyob rau hauv qhov cim thiab pH

PVA 2488’s dissolution kinetics yog tshaj tshuaj ntau dua li cas los ntawm nws 88% hydrolysis level—tsis txhob tso cia acetate groups ntau dua li xav tau los ntawm kev tswj hwm qhov tshuaj tshaj tshuaj. Thaum 20°C, cov films tshaj tshuaj hauv sij hawm ib leeg; thaum 5°C, kev tshaj tshuaj yuav nyob hauv sij hawm ob peb feeb vim kev hydrogen bonding nrog dej yuav ntaus dua. Cov xim alkaline (pH 9–11) yuav pab tshaj tshuaj dua li ntawm kev hydrolysis ntawm acetate uas muaj base-catalyzed, tab sis cov xim acidic (pH 3–5) yuav tshem tawm kev tshaj tshuaj vim kev protonation ntawm hydroxyl groups, uas ua rau kev mob ntawm cov chains yuav ntaus dua. Cov lus tshaj tshuaj no pab cov neeg tsim tshuaj kom tuaj yeem tsim cov kev tshaj tshuaj uas muaj kev tswj hwm—vim rau cov detergent pods uas tshaj tshuaj hauv dej ntseeg lossis cov agrochemical sachets uas xav tau kev tshaj tshuaj tom qab hauv dej ntawm lub vaj.

Cold-Water-Soluble Detergent Pods thiab Agrochemical Sachets uas muaj PVA 2488

PVA 2488 yog li cov ntaub ntawv uas tswj hwm rau kev ua cov duab thiab cov duab tshuaj tshuaj uas muaj ntau yam tshuaj tshuaj. Nws tuaj yeem tshem tau txhua yam nyob rau hauv 10°C, yog li nws tuaj yeem tshem tau txhua yam tshuaj tshuaj thiab cov duab tshuaj rau kev ua tshuaj tshuaj. Rau kev siv hauv kev ua tshuaj tshuaj, cov duab tshuaj yog li cov ntaub ntawv uas pheej yig rau kev tshem tshuaj tshuaj thiab cov tshuaj tshuaj uas tshem tau thaum muaj dej. Nws tuaj yeem tshem tau cov tshuaj tshuaj thiab cov tshuaj tshuaj uas tsis muaj kev nyuaj siab rau cov neeg siv. Qhov no tuaj yeem pab tshem tau kev siv tshuaj tshuaj raws li qhov xav thiab tshem tau kev siv cov ntaub ntawv plastic rau kev siv hauv cov ntaub ntawv uas muaj ntau yam ntaub ntawv. Txhawm rau pab tshem tau kev siv tshuaj tshuaj, PVA 2488 tuaj yeem tshem tau nyob rau hauv cov ntaub ntawv uas muaj dej thiab cov ntaub ntawv uas muaj dej.

Kev tswj hwm rau kev tshem tshuaj tshuaj: Kev tswj hwm rau kev tshem tshuaj tshuaj thiab kev tswj hwm rau kev tshem tshuaj tshuaj

Kev tswj hwm rau kev tshem tshuaj tshuaj thiab kev tswj hwm rau kev tshem tshuaj tshuaj rau PVA 2488

PVA 2488 tuaj yeem tswj qhov kub thiab qhov ntxiv ntawm oxygen hauv qhov chaw uas tsis muaj dej—yog li cas, qhov ntxiv ntawm oxygen (OTR) yuav tshwm sim rau hauv 0.02 cc/m²/day nyob rau hauv qhov kub thiab qhov ntxiv ntawm dej uas yooj dua, raws li kev siv ASTM D3985 uas yog kev siv ua siab xyuas. Tiamsi, qhov ntxiv ntawm dej ntawm PVA 2488 yuav tshwm sim thaum qhov kub thiab qhov ntxiv ntawm dej nyob hauv qhov chaw yuav nce, uas yuav tshwm sim qhov ntxiv ntawm dej thiab qhov ntsuas ntawm cov hydrogen bonds. Qhov 88% hydrolysis yuav tshwm sim qhov ntsuas ntawm crystallinity uas yuav tshwm sim qhov ntsuas ntawm qhov ntxiv ntawm dej thiab yuav tshwm sim qhov ntxiv ntawm water vapor transmission rate (WVTR) rau hauv 0.02–0.05 g/m²/day nyob rau hauv qhov kub thiab qhov ntxiv ntawm dej uas yooj dua. Qhov no yuav tshwm sim qhov tswv yim uas tau muab txhais rau lawm: qhov tswv yim zoo heev rau qhov ntxiv ntawm oxygen thaum tsis muaj dej, tab sis qhov tswv yim yuav nce ntau thaum qhov kub thiab qhov ntxiv ntawm dej yog 60% RH los ntawd—a behavior uas tau muab siv rau lwm cov bio-based barriers li cellulose derivatives.

Tshem tawm qhov ntxiv ntawm dej uas tshwm sim qhov ntsuas ntawm barrier los ntawm kev sib npaug thiab kev siv coating

Los ntawv tshuaj no siv rau kom PVA 2488 muaj kev kub thiab kev tswj hluav taws xob nyob rau hauv qhov chaw uas muaj dej ntau. Lub thawj yam, siv cov ntawv tshuaj uas tsis nyob rau hauv dej—piv txwv li polylactic acid (PLA) lossis ethylene-vinyl alcohol (EVOH)—los ua kom cov ntawv tshuaj tsis nyob rau hauv dej ntau dua, thiab tso cia cov kev kub thiab kev tswj hluav taws xob ntawm PVA. Lub ob yam, siv cov ntawv tshuaj los pab kom cov ntawv tshuaj nyob ib leeg—piv txwv li glyoxal lossis glutaraldehyde—los ua kom cov ntawv tshuaj tsis tuaj yeem los ntawm dej thiab tsis tuaj yeem los ntawm kev nqus, thiab tso cia cov ntawv tshuaj nyob ib leeg. Lub peb yam—uas yog qhov zoo tshaj plaws—siv lub tshuab ntxiv (piv txwv li wax los ntawm nplooj ntawv, lipid emulsion, lossis polyvinylidene chloride) los ua lub tshuab ntxiv uas tsis nyob rau hauv dej, thiab lub tshuab ntxiv no pab kom PVA tsis tau dej nyob rau hauv. Lub tshuab ntxiv no muaj kev sib thag rau cov tshuab ntxiv uas muaj nyob rau hauv nplooj ntawv thiab muaj kev sib thag rau cov tshuab ntxiv uas muaj nyob rau hauv nplooj ntawv, thiab lub tshuab ntxiv no pab kom cov neeg siv tshuab ntxiv tuaj yeem tswj kom OTR tsis meej dua 0.1 cc/m²/day nyob rau hauv qhov chaw uas muaj dej ntau dua 75% RH, thiab lub tshuab ntxiv no pab kom tuaj yeem siv rau cov khoom uas muaj dej ntau thiab cov khoom uas muaj kev tswj hluav taws xob nyob rau hauv qhov chaw uas muaj dej ntau.

Kev pab kom cov ntawv tshuaj nyob ib leeg thiab kev sib thag rau cov ntawv tshuaj uas muaj kev sib thag

Kev ntxuav qhov txaus (55–65 MPa) thiab kev ntxuav qhov ntsuas (150–200%) ua rau cov khoom siv ntawm kev kho cov khoom zoo dua

Cov phaj PVA 2488 muaj qhov txaus siab (55–65 MPa) thiab qhov ntsuas siab (150–200%), uas muaj kev plooj pliag ntawm kev txaus thiab kev ntsuas. Qhov no ua rau cov khoom tuaj yeem tshuav kev txhawb nqa thaum kho, khiav, thiab khiav rau hauv tsev kho khoom tsis tau txais kev puas thiab kev tawg. Qhov ntsuas siab tuaj yeem tshuav kev tawg los ntawm kev tshuav, thiab qhov txaus tuaj yeem tshuav kev tawg los ntawm kev tshuav. Hauv cov phaj ntau daim, PVA 2488 ua rau cov phaj zoo dua—ua rau cov phaj tsis tau tawg, cov phaj zoo dua hauv qhov rov, thiab cov phaj zoo dua. Qhov txaus thiab qhov ntsuas zoo tuaj yeem tshuav kev tshuav ntawm cov phaj, uas ua rau cov phaj tsis tau tawg thaum tshuav. Thaum cov phaj tsis tau tawg thaum tshuav, PVA 2488 ua rau cov phaj zoo dua—ua rau cov phaj yooj yim dua thiab tsis tau txais kev puas thaum kho cov khoom hauv kev khiav ntau yam.

FAQ

PVA 2488 yog dab tsi?

PVA 2488 yog li tswv yim ntawm polyvinyl alcohol uas tau muab hydrolyzed rau qhov tseem ceeb 88%. Nws yog qhov tshuaj uas tsim rau kev siv uas xav tau cov khoom uas tuaj yeem dissolving hauv dej, muaj qhov zoo tshaj plaws rau kev khaub ncaws, thiab muaj qhov zoo tshaj plaws rau kev tiv thaiv.

PVA 2488 ua li cas kom cov khoom siv ib zaug tuaj yeem tiv thaiv?

PVA 2488 muaj qhov zoo tshaj plaws rau kev dissolving nyob rau hauv dej ntsuag thiab pH, yog li nws yog qhov zoo tshaj plaws rau cov khoom siv detergent pod uas tuaj yeem dissolving hauv dej ntsuag thiab cov khoom siv agrochemical sachets. Nws pab zam cov khoom siv plastic uas tsis tuaj yeem ncaj ncees, kom txog qhov ntau dua rau kev tiv thaiv plastic, thiab nws tuaj yeem tiv thaiv hauv cov khoom siv wastewater.

PVA 2488 muaj qhov zoo tshaj plaws li cas rau kev tiv thaiv moisture thiab oxygen?

PVA 2488 muaj qhov zoo tshaj plaws rau kev tiv thaiv oxygen nyob rau hauv qhov tshav tshav, tab sis nws muaj qhov tshav tshav dua rau kev tiv thaiv moisture vapor thaum qhov humidity ncaj ncees. Cov kev siv blending thiab coating yuav pab tiv thaiv qhov no.

Yog li cas PVA 2488-coated materials tuaj yeem recycled?

Yog, cov khoom siv uas muaj PVA 2488 coating tuaj yeem recycled thiab repulpable, vim tias cov coating yuav tiv thaiv hauv cov hydropulping systems, kom muaj kev siv circular packaging.