Yog li cas xaiv polyvinyl alcohol (PVA) uas muaj kev ntsuas tau zoo rau kev tsim adhesive

Sib tham cov leeg PVA thiab cov khoom siv adhesive

Peej tshem cov leeg polyvinyl alcohol (PVA 17-88, 24-88, 0588, 088-07) rau hais cov khoom siv adhesive rau cov ntawv, cov khoom siv rau lub tsev, cov khoom siv rau cov ntaub, thiab cov khoom siv rau cov duab

Kuam txawj ntse ntawm kev xaiv cov PVA (polyvinyl alcohol) uas muaj qhov zoo tshaj plaws yuav sib npaug rau qhov ua haujlwm ntawm cov adhesive—y especially rau qhov ua kom muaj qhov ceev, qhov ua kom haum, qhov ua kom rov los ua kom haum, thiab qhov ua kom tsis muaj kev nyab xeeb los ntawm qhov chaw. Rau cov adhesive rau lub ntawv—tswv yim li cas nyob rau hauv cov ntawv tshuab thiab cov ntawv uas tau muab faib los ua—cov PVA 0588 (88% hydrolyzed) uas muaj qhov viscosity ntsib, thiab muaj qhov molecular weight ntsib, yuav pab ua kom haum ntau thiab ua kom rov los ua kom haum ntau. Rau cov adhesive rau kev ua cov dej thiab cov ntawv—cov adhesive yuav tsum muaj qhov ceev ntau thiab yuav tsum muaj kev nkag mus rau hauv cov ntawv ntau; cov PVA 24-88 yuav pab ua raws li cov teeb meem no los ntawm qhov molecular weight ntau thiab qhov film toughness ntau. Rau cov sizing rau cov ntawv—cov partial hydrolysis yuav pab ua kom muaj qhov haum thiab qhov adhesion rau cov fiber; cov PVA 17-88 yuav pab ua kom muaj qhov haum ntau rau cov synthetic warp yarns thiab pab ua kom muaj qhov residue ntsib rau hauv qhov desizing. Rau cov adhesive rau cov paint rau hauv tsev—cov adhesive yuav tsum muaj qhov clarity thiab qhov resistance rau cov moisture; cov PVA 088-07 uas tau hydrolyzed ntau yuav pab ua kom muaj qhov film integrity ntau thiab qhov durability ntau thaum ua haujlwm ntev, thiab tsis muaj qhov yellowing. Qhov tseem ceeb tshaj plaws yog: qhov viscosity thiab qhov hydrolysis degree yuav tsum haum rau cov substrate porosity thiab cov processing parameters: qhov hydrolysis ntsib yuav pab ua kom muaj qhov solubility ntau rau cov cold-water, thiab qhov molecular weight ntau yuav pab ua kom muaj qhov melt viscosity thiab qhov cohesive strength ntau. Kev haum rau cov intrinsic properties no rau cov teeb meem ntawm kev ua haujlwm yuav tsum muaj qhov tseem ceeb rau kev design cov adhesive uas muaj qhov ua haujlwm zoo.

Cov ntaub ntawv tswj yim uas tsis tuaj yeem los ntawm cov qhia txog cov ntaub ntawv

Cov qhia txog cov ntaub ntawv xwb tsis tuaj yeem pab kom cov adhesive ua haujlwm zoo tshaj plaws rau hauv kev tsim. Peb qhov cim tswj yim—qhib cov ntaub ntawv, kev nyuaj siab thiab kev nyuaj ntawm lub neej—tsis tuaj yeem pab kom cov adhesive ua haujlwm zoo thiab muaj kev nyuaj siab rau hauv kev siv nyob hauv qhov kev nyuaj siab.

Qhib cov ntaub ntawv, kev nyuaj siab thiab kev nyuaj ntawm lub neej rau hauv kev siv adhesive nyob hauv qhov kev nyuaj siab

Kev ua haujlwm ntawm cov ntaub ntawv tshuab (film-forming ability) yuav tso cai rau PVA kom muaj kev kawm thiab kawm zoo li cas, kawm zoo li cas, thiab kawm los ntawm qhov chaw uas nws tau kawm—tsis tuaj yeem txhawb rau kev kawm zoo li cas, qhov ntawv, thiab kev kawm zoo li cas. Yog tias kev kawm tsis zoo, nws yuav ua rau qhov chaw kawm tsis zoo, tias yuav tshwm sim rau qhov chaw uas tsis zoo thiab qhov chaw uas tsis muaj kev kawm zoo. Kev nyob zoo ntawm qhov ceev (thermal stability) yog qhov tswv yim rau qhov kawm ntau dua, qhov kawm ntau dua rau qhov ceev, thiab qhov kawm ntau dua rau qhov ceev; PVA uas tsis muaj kev nyob zoo rau qhov ceev yuav tshwm sim rau kev puas qhov ntaub ntawv, uas yuav ua rau kev puas qhov ntaub ntawv thiab kev puas qhov kawm zoo li cas. Kev nyob zoo rau qhov xyoob (aging resistance) yog qhov tswv yim rau qhov kawm uas tau kawm zoo li cas, thiab yuav tshwm sim rau qhov xyoob, qhov ceev, thiab qhov xyoob rau UV. Rau qhov kawm ntawm qhov ntaub ntawv, qhov kawm tsis zoo rau qhov xyoob yuav tshwm sim rau qhov kawm tsis zoo li cas; rau qhov kawm ntawm qhov ntaub ntawv, qhov kawm tsis zoo rau qhov xyoob yuav tshwm sim rau qhov kawm tsis zoo li cas thiab qhov kawm tsis zoo li cas rau qhov ntaub ntawv rau qhov kawm. Cov lus no tsis tau txais rau qhov kawm zoo li cas rau qhov kawm zoo li cas—thiab yuav tsum tau txais rau qhov kawm zoo li cas rau qhov kawm zoo li cas rau qhov kawm zoo li cas thiab qhov kawm zoo li cas rau qhov kawm zoo li cas.

Kho siab txog kev txaus siab ntawm Polyvinyl Alcohol los ntawm kev kho kom meej

Kho siab raws li kev kawm: kev soj ntsuam qhov soj ntsuam → kev soj ntsuam qhov ua haujlwm → kev soj ntsuam qhov ua haujlwm thiab kev soj ntsuam qhov tsis tau soj ntsuam

Qhov kev sib txuas PVA uas muaj zog ntau yuav tsum pib ntawm qhov kev ua kom zoo thiab kev ua kom zoo raws li qhov kev ua kom zoo—tsis yog tso cia rau qhov kev paub tias cov neeg siv khoom tau muaj lub npe. Qhov kev test solubility yuav tsum ua ua ntej kom paub tias qhov khoom tau rov ua dua lawm thiab tau rov ua dua los ntawm qhov cim uas muaj qhov cim ntawm qhov hluav tais, pH, thiab qhov kev txiav txim; qhov khoom uas tsis tau rov ua dua yuav tshwm sim rau qhov kev sib txuas tsis zoo lossis muaj khoom tsis zoo, uas yuav cuam ntxiv rau qhov kev cua khaub ncua thiab qhov kev sib txuas tsis zoo. Tom qab ntawd, qhov kev ua kom paub tias qhov viscosity yuav tsum ua kom paub tias qhov viscosity yog li cas ntawm qhov kev txiav txim ntawm qhov kev txiav txim; kom paub tias qhov kev txiav txim yog li cas—uas yog qhov tseem ceeb rau qhov kev txiav txim zoo, qhov kev txiav txim zoo thiab qhov kev txiav txim rau qhov kev txiav txim. Tom qab ntawd, qhov kev ua kom paub tias qhov bond strength yuav tsum ua kom paub tias qhov kev txiav txim yog li cas ntawm qhov kev ua kom paub tias qhov kev txiav txim (piv txwv li ASTM D903 peel lossis D1876 T-peel tests) kom paub tias qhov kev txiav txim yog li cas ntawm qhov kev txiav txim uas muaj qhov kev txiav txim. Thaum thaum, qhov kev ua kom paub tias qhov water resistance—ua los ntawm qhov kev txiav txim ntawm qhov kev txiav txim (piv txwv li ASTM D2247) lossis qhov kev txiav txim—kom paub tias qhov kev txiav txim yog li cas ntawm qhov kev txiav txim. Qhov kev ua kom paub tias qhov kev txiav txim yog li cas yuav tshwm sim rau qhov kev txiav txim zoo, txhawm rau txhawm rau qhov kev txiav txim tsis zoo thiab kom paub tias qhov PVA uas tau xa tuaj yog li cas thiab kom paub tias qhov kev txiav txim yog li cas ntawm qhov kev txiav txim.

FAQ

Yus li cas yog qhov tseem ceeb ntawm kev hloov nqaij rau polyvinyl alcohol?

Qhov hloov nqaij txuas lub tswv yim ntawm PVA cov lus siv thiab cov lus khib rau dej. Qhov hloov nqaij tsis loo yuav pab tshem tias nws yuav siv tau rau dej ntug, thaum qhov hloov nqaij loo yuav pab tshem tias nws muaj kev nyab xeeb thiab kev nyab xeeb rau qhov chaw.

Cia li cas yog qhov tseem ceeb rau kev ua kom paub tias PVA yuav ua haujlwm zoo?

Kev paub tias yuav ua haujlwm zoo yuav pab tshem tias kev siv adhesive yuav zoo ib yam los ntawm kev test cov lus siv thiab kev ua haujlwm, puav leej, kev nyab xeeb thiab kev khib rau dej. Vim li no, nws yuav pab tshem tias muaj kev ua haujlwm tsis zoo thiab pab tshem tias muaj kev ua haujlwm zoo thiab muaj kev ua haujlwm zoo rau hauv qhov chaw.

Cia li cas yog qhov tseem ceeb ntawm kev ua film rau kev siv adhesive?

Qhov ua film yuav pab tshem tias adhesive yuav siv tau zoo li cas rau kev siv, kev sov thiab kev nyab xeeb rau cov khoom. Qhov ua film tsis zoo yuav pab tshem tias muaj cov cim tsis zoo, uas yuav pab tshem tias kev nyab xeeb thiab kev nyab xeeb tsis zoo.

Cia li cas yog cov kev test uas tuaj yeem muaj kev ua kom paub tias kev nyab xeeb zoo?

Cov kev test standard li ASTM D903 peel tests lossis D1876 T-peel tests yuav pab sim kev ua haujlwm rau kev nyab xeeb thiab pab tshem tias kev nyab xeeb zoo.