Intshayelelo kwi-PBT

I-Polybutylene terephthalate (i-PBT emfutshane) luhlu lwee-polyester, ezenziwe nge-1.4-pbt butylene glycol kunye ne-terephthalic acid (PTA) okanye i-terephthalic acid ester (DMT) nge-polycondensation, kwaye yenziwe nge-milky white ngokusebenzisa inkqubo yokuxuba.Ukutshintshela kwi-opaque, i-crystalline thermoplastic polyester resin.Kunye ne-PET, yaziwa ngokudibeneyo njenge-thermoplastic polyester, okanye ipolyester egcweleyo.

I-PBT yaphuhliswa okokuqala ngusosayensi waseJamani uP. Schlack ngo-1942, emva koko yaphuhliswa kwimizi-mveliso yiCelanese Corporation (ngoku eyiTicona) yaza yathengiswa phantsi kwegama lorhwebo iCelanex, eyasungulwa ngo-1970 njenge-30% yeglasi yefiber eyomeleziweyo yeplastiki phantsi kwegama lezorhwebo elithi X- 917, kamva yatshintshelwa kwi-CELANEX.U-Eastman uqalise imveliso kunye nangaphandle kwe-glass fiber reinforcement, phantsi kwegama lezorhwebo elithi Tenite (PTMT);kwakulo nyaka, i-GE iphinde yavelisa imveliso efanayo eneentlobo ezintathu zokungaqini, uqiniswa kunye nokuzicima.Emva koko, abavelisi abadumileyo behlabathi abanje ngeBASF, Bayer, GE, Ticona, Toray, Mitsubishi Chemical, Taiwan Shin Kong Hefei, Changchun Synthetic Resins, kunye neNanya Plastics baye bangena ngokulandelelana kwimigangatho yemveliso, kwaye kukho ngaphezu kwe30 abavelisi kwihlabathi liphela.

Njengoko i-PBT inokumelana nokushisa, ukumelana nemozulu, ukuchasana kweekhemikhali, iimpawu ezintle zombane, ukufunxa kwamanzi aphantsi, i-gloss enhle, esetyenziswa ngokubanzi kwizixhobo zombane, iimoto zemoto, oomatshini, iimveliso zendlu, njl., kunye neemveliso ze-PBT kunye ne-PPE, i-PC, i-POM, PA, njl. ndawonye zaziwa njengeeplastiki ezinkulu ezintlanu zobunjineli jikelele.Isantya sekristallisation ye-PBT, eyona ndlela ifanelekileyo yokusetyenzwa kukubumba inaliti, ezinye iindlela zi-extrusion, ukubumba ukuvuthela, ukugquma, njl.

Umda wesicelo oqhelekileyo

Izixhobo zasendlini (iincakuba ezilungisa ukutya, izinto zokufunxa, iifeni zombane, amaqokobhe ezomisi iinwele, izixhobo zekofu, njl.njl.), izinto zombane (iiswitshi, izindlu zeemoto, iibhokisi zefuse, izitshixo zebhodi yezitshixo zekhompyutha, njl. njl.), ishishini lemoto (izakhelo zokulungisa izibane , iifestile ze-radiator grille, iipaneli zomzimba, izigqubuthelo zamavili, izinto zocango kunye neefestile, njl.).

Iimpawu zemichiza kunye nezomzimba

I-PBT yenye yezona zinto zinzima zobunjineli be-thermoplastics, yimathiriyeli ye-semi-crystalline enozinzo oluhle kakhulu lweekhemikhali, amandla omatshini, iipropati zokugquma umbane kunye nokuzinza kwe-thermal.pbt inozinzo oluhle phantsi kweemeko zokusingqongileyo.I-pbt ineempawu ezibuthathaka kakhulu zokufunxa ukufuma.Amandla e-tensile ye-PBT engaqiniswanga yi-50 MPa, kunye nokuqina kwe-glass fiber additive type PBT yi-170 MPa.Iglasi eninzi yokongeza ifayibha iya kubangela ukuba izinto zibe brittle.icrystallization ye-PBT ikhawuleza kakhulu, kwaye ukupholisa okungalinganiyo kuya kubangela ukugoba ukugoba.Kwizinto eziphathekayo kunye nohlobo lwe-glass fiber additive, izinga lokunciphisa kwindlela yenkqubo lingancitshiswa, kwaye izinga lokunciphisa kwinqanaba elithe tye alikho ngokwahlukileyo kwizinto eziqhelekileyo.Izinga lokuncipha kwezinto eziqhelekileyo ze-PBT ziphakathi kwe-1.5% kunye ne-2.8%.I-shrinkage yezinto eziqulethe i-30% ye-glass fiber additives iphakathi kwe-0.3% kunye ne-1.6%.

Iimpawu zenkqubo yokubumba inaliti ye-PBT

Inkqubo ye-polymerization ye-PBT ikhulile, ixabiso eliphantsi kwaye kulula ukubumba kunye nokusebenza.Ukusebenza kwe-PBT engaguqukiyo ayilungile, kwaye ukusetyenziswa kwangempela kwe-PBT kufuneka kuguqulwe, apho, i-fiber yeglasi eqiniswe ngamabakala aguquliweyo angaphezulu kwe-70% ye-PBT.

I-1, i-PBT inendawo ecacileyo yokunyibilika, indawo yokunyibilika ye-225 ~ 235 ℃, i-crystalline material, i-crystallinity ukuya kwi-40%.i-viscosity ye-PBT yokunyibilika ayichatshazelwa bubushushu njengoxinzelelo lwe-shear, ngoko ke, ekubunjweni kwenaliti, uxinzelelo lwenaliti kwi-PBT lunyibilike ulwelo olucacileyo.I-PBT kwimo etyhidiweyo ye-fluidity enhle, i-viscosity ephantsi, yesibini kuphela kwi-nylon, ekubunjweni kulula ukwenzeka "Iimveliso ezibunjiweyo ze-PBT ziyi-anisotropic, kwaye i-PBT kulula ukuthotywa phantsi kobushushu obuphezulu xa udibana namanzi.

2. Umatshini wokubumba wokutofa

Xa ukhetha umatshini wokubumba we-screw type.Ezi ngongoma zilandelayo zifanele ziqwalaselwe.

① Ubungakanani bezinto ezisetyenzisiweyo kwimveliso kufuneka zilawulwe kwi-30% ukuya kwi-80% yomthamo olinganisiweyo wenaliti ephezulu yomatshini wokubumba inaliti.Akufanelekanga ukusebenzisa umatshini wokubumba inaliti enkulu ukuvelisa iimveliso ezincinci.

② kufuneka ikhethwe nge-screw yamanqanaba amathathu ngokuthe ngcembe, ubude ukuya kwi-diameter ratio ye-15-20, i-compression ratio ye-2.5 ukuya kwi-3.0.

③Kungcono ukusebenzisa umbhobho wokuzivalela ngokufudumeza kunye nesixhobo sokulawula ubushushu.

④Ekubumbeni i-PBT ye-flame retardant, iindawo ezifanelekileyo zomatshini wokubumba inaliti kufuneka ziphathwe nge-anti-corrosion.

3, imveliso kunye noyilo lokungunda

① Ubukhulu beemveliso akufunekanga bube bukhulu kakhulu, kwaye i-PBT inovakalelo kwinotshi, ngoko ke iindawo eziguqukayo ezifana ne-angle elungileyo yeemveliso kufuneka ziqhagamshelwe ngee-arcs.

②I-shrinkage yokubumba ye-PBT engalungiswanga inkulu, kwaye isikhunta kufuneka sibe ne-slope ethile yokudiliza.

③Umngundo kufuneka uxhotyiswe ngemingxunya yokukhupha okanye izithuba zokuphuma.

④Ubukhulu besango kufuneka bube bukhulu.Kunconywa ukusebenzisa abagijimi beesetyhula ukwandisa ukutshintshwa koxinzelelo.Iindidi ezahlukeneyo zamasango zinokusetyenziswa kwaye iimbaleki ezishushu nazo zingasetyenziswa.Ububanzi besango kufuneka bube phakathi kwe-0.8 kunye ne-1.0 * t, apho i-t ibubukhulu benxalenye yeplastiki.Kwimeko yamasango aphantsi kwamanzi, ubuncinane be-diameter ye-0.75mm iyacetyiswa.

⑤ Umngundo kufuneka uxhotyiswe ngesixhobo sokulawula ubushushu.Ubushushu obuphezulu bomngundo akufunekanga budlule kwi-100℃.

⑥Ukwenzela ukubumba i-PBT ye-flame retardant, umphezulu wokungunda kufuneka ufakwe nge-chrome ukunqanda ukubola.

Ukusetwa kweeparamitha zenkqubo

Ukomisa unyango: Izinto ze-PBT zifakwe ngokulula kwi-hydrolyzed kwiqondo lokushisa eliphezulu, ngoko kufuneka zomiswe ngaphambi kokuba zicutshungulwe.Kunconywa ukomisa emoyeni oshushu kwi-120 ℃ kwiiyure ze-4, kwaye ukufuma kufuneka kube ngaphantsi kwe-0.03%.

Ubushushu obunyibilikayo: 225℃～275℃, ubushushu obucetyiswayo: 250℃.

Ubushushu bomngundo: 40℃～60℃ kwizinto ezingaqiniswanga.Ukupholisa umngundo kufuneka kufane ukunciphisa ukugoba kwamalungu eplastiki, kunye nedayamitha ecetyiswayo yejelo lomngxunya lokupholisa yi-12mm.

Uxinzelelo lwe-injection: phakathi (ngokubanzi i-50 ukuya kwi-100MPa, ubuninzi ukuya kwi-150MPa).

Isantya sokutofa: Isantya sokutofa isantya sokupholisa se-PBT siyakhawuleza, ngoko ke kufuneka kusetyenziswe isantya esikhawulezayo sokutofa.Elona nqanaba likhawulezayo lokutofa kufuneka lisetyenziswe (kuba i-PBT iqina ngokukhawuleza).

Isantya se-Screw kunye noxinzelelo lwangasemva: Isantya se-screw sokubumba i-PBT akufanele sidlule i-80r / min, kwaye ngokubanzi phakathi kwe-25 kunye ne-60r / min.Uxinzelelo lwangasemva luyi-10% -15% yoxinzelelo lwenaliti.

Ingqalelo

① Ukusetyenziswa kwemathiriyeli ephinda isetyenziswe Umlinganiselo wemathiriyeli esetyenzisiweyo kwimathiriyeli entsha ikholisa ukuba yi-25% ukuya kwi-75%.

② Ukusetyenziswa kwe-ejenti yokukhululwa kwe-mold Ngokuqhelekileyo, akukho arhente yokukhupha i-mold isetyenzisiweyo, kunye ne-agent ye-silicone yokukhululwa kwe-mold ingasetyenziswa ukuba kuyimfuneko.

③Ukucinywa kwenkqubo Ixesha lokuvalwa kwe-PBT lingaphakathi kwe-30min, kwaye ubushushu bunokuthotywa ukuya kwi-200℃ xa kuvalwa.Xa uvelisa kwakhona emva kokuvala ixesha elide, izinto ezikwi-barrel kufuneka zikhutshwe kwaye ke izinto ezintsha kufuneka zongezwe kwimveliso eqhelekileyo.

④ Emva kokulungiswa kweemveliso Ngokuqhelekileyo, akukho nyango lufunekayo, kwaye ukuba kuyimfuneko, unyango lwe-1 ~ 2h kwi-120℃.

PBT isikrufu esikhethekileyo

Kwi-PBT, ekulula ukubola, ukunyamezela uxinzelelo kunye neemfuno zokongeza i-fiber yeglasi, i-PBT ekhethekileyo i-screw ivelisa uxinzelelo oluzinzile kwaye isebenzisa i-alloy ephindwe kabini ukuphucula ukuxhatshazwa kwezinto eziphathekayo nge-glass fiber (PBT + GF).