isicelo

I-LDPE iyi-ai-polyethylene ephansi, elungiswa yi-polymerization ye-ethylene monomer eyenziwe yi-free radical initiator futhi ayiqukethe noma iyiphi enye i-copolymer.Izici zayo zamangqamuzana ziyizinga eliphezulu kakhulu le-branching, nenani elikhulu lamaketanga amade amagatsha, ngenxa yokuhlangana okuhlangene kwamaketanga amangqamuzana, ukuze ukuqina kwawo kungabi namandla, angeke kube ingxenye enkulu yokwelula, ikhono lomthelela ophansi.

Ngesikhathi esifanayo, ngenxa yezinga eliphezulu le-branching, linamandla aphezulu ancibilika, adlala indima enkulu ekuqiniseni i-bubble ye-membrane.Ngenxa yokuvuleka kwe-molecule enqubweni yokugunda, inezici ezicacile zokunciphisa i-shear, futhi i-viscosity encibilikayo iyancipha kakhulu ekusheleni okuphezulu, okuletha ukusebenza okuhle kokucutshungulwa kwe-extrusion, okubonakala njengengcindezi ephansi yokuncibilika, izinga lokushisa eliphansi lokuncibilika kanye nomthwalo wemoto. .

Ngenxa yezici ezingenhla, i-LDPE ingasetshenziswa ngendlela eguquguqukayo ekwakhiweni kokwakhiwa ukuze kuzuzwe ukusebenza okufunayo.Kukhona ikakhulukazi izici ezilandelayo:

1. Thuthukisa ukusebenza kwemishini

Ngokukhula kwezidingo zemakethe zokupakisha, ukusetshenziswa kwe-metallocene nakho kukhulu kakhulu, nakuba ukusebenza kwe-metallocene kuhle kakhulu, kodwa ukucubungula kuvame izimbambo zayo ezithambile, ngokuvamile kuyinqubo ye-extrusion ukukhiqiza ukushisa kwe-shear ngokweqile, ingcindezi. ukwanda, izinga lokushisa liyakhuphuka, ibhamuza le-membrane alizinzile.Lokhu kungathuthukiswa ngokuxuba i-LDPE, isilinganiso sokwengeza singaba ngu-15-30%, uma isilinganiso sokwengeza siphezulu kakhulu, sizothinta ngokuqondile izakhiwo zokugcina zomzimba zefilimu, okudingeka zilinganiswe.

2. Thuthukisa ukusebenza kwe-optical

Amanye amafilimu anezidingo ezithile zezakhiwo ze-optical.I-Linear noma i-metallocene LLDPE inezici ezijwayelekile zokubona, ikakhulukazi ngenxa yokuthi ukukhula kwayo kwangaphakathi kwekristalu kukhulu kakhulu.Uma i-5-15% LDPE yengezwa kuyo, izosiza ukunciphisa usayizi wekristalu yangaphakathi, ukuze kuthuthukiswe inkungu nokungafihli.

3. Thuthukisa ukusebenza kophawu lokushisa

Ukusebenza kokubeka uphawu okushisayo kwe-linear noma i-metallocene LLDPE kungcono kakhulu kunokwe-LDPE.Kodwa-ke, ngenxa yesakhiwo sezinga eliphezulu le-branched kanye ne-viscosity ephezulu yokuncibilika ku-shear ephansi, i-LDPE ingavimbela amaphutha okuvalwa kokushisa okubangelwa ukukhishwa ngokweqile kwefilimu yokuvala ukushisa ngesikhathi sokuvalwa kokushisa.Ngesikhathi esifanayo, inani elifanele le-LDPE lingathuthukisa amandla okubopha okushisayo, kodwa inani akufanele libe liningi kakhulu.Uma kungenjalo, kuzokwenza uphawu lokushisa lube lubi nakakhulu.

4. Okunye ukuthuthukiswa kokusebenza

Isibonelo, kufilimu ye-shrinkage ukuthuthukisa ukuncipha okushisayo kanye nesilinganiso sokunciphisa;Isimo sokumaka amahlosi singathuthukiswa ngefilimu ephendukayo.Ukuthuthukisa i-necking phenomenon ku-casting film;Esikhathini ifilimu abamba ukushisa ukuthuthukisa ukuzinza ulwelwesi bubble ukuze kuzuzwe ukukhiqizwa ulwelwesi ngezinga elikhulu, nokunye.

Kungabonakala ukuthi i-LDPE idlala indima ebalulekile ekwakhiweni kwamafilimu amancanyana ngenxa yesakhiwo sawo esikhethekile samangqamuzana, futhi ukuhlanganiswa okunengqondo nezinye izinto ze-polymer kungafeza ukuthuthukiswa kokubunjwa kanye nokwenza ngcono ukusebenza.