Mold ɗin filastik gajeriyar hanya ce ta mold da aka haɗa da ake amfani da shi don molding na matsewa, molding na extrusion, allura, molding na busawa da ƙarancin kumfa. Canje-canjen da aka daidaita na mold convex da concave molds da tsarin molding na taimako na iya sarrafa jerin sassan filastik masu siffofi daban-daban da girma dabam-dabam. Molds ɗin filastik sune uwar masana'antu, kuma sabbin samfuran da aka fitar yanzu sun haɗa da robobi.

Ya ƙunshi galibin mold na mace mai rami mai canzawa wanda ya ƙunshi mold na mace, ɓangaren mold na mace da allon kati mai haɗin mold na mace, da kuma haɗin mold mai convex, ɓangaren mold mai convex, allon kati mai haɗin mold na namiji, ɓangaren yanke rami da kuma naushi mai tsakiya mai canzawa wanda ya ƙunshi faranti masu haɗin gefe.
Domin inganta aikin robobi, dole ne a ƙara kayan taimako daban-daban, kamar su cika, masu tace robobi, mai, masu daidaita abubuwa, masu launi, da sauransu, a cikin polymer ɗin don su zama robobi masu aiki mai kyau.

1. Resin roba shine mafi mahimmancin ɓangaren robobi, kuma abun da ke cikinsa a cikin robobi gabaɗaya shine 40% zuwa 100%. Saboda abun da ke ciki yana da girma, kuma yanayin resin sau da yawa yana ƙayyade yanayin robobi, mutane sau da yawa suna ɗaukar resin a matsayin ma'anar robobi. Misali, rikitar da resin polyvinyl chloride da robobi polyvinyl chloride, da resin phenolic da robobi phenolic. A zahiri, resin da robobi ra'ayoyi ne daban-daban guda biyu. Resin wani polymer ne da ba a sarrafa shi ba wanda ba wai kawai ake amfani da shi don yin robobi ba, har ma da kayan aiki don rufewa, mannewa, da zare na roba. Baya ga ƙaramin ɓangare na robobi wanda ke ɗauke da resin 100%, yawancin robobi suna buƙatar wasu abubuwa ban da babban resin.

2. Ana kuma kiran Filler Filler da filler, wanda zai iya inganta ƙarfi da juriyar zafi na robobi da rage farashi. Misali, ƙara foda na itace a cikin resin phenolic zai iya rage farashi sosai, yana mai da filastik phenolic ɗaya daga cikin robobi mafi arha, yayin da kuma inganta ƙarfin injina sosai. Ana iya raba fillers zuwa nau'i biyu: fillers na halitta da fillers marasa tsari, na farko kamar fulawar itace, tsummoki, takarda da zare daban-daban na masana'anta, na biyu kuma kamar fiber gilashi, ƙasa mai kama da diatomaceous, asbestos, da carbon black.

3. Masu yin filastik. Masu yin filastik na iya ƙara ƙarfin filastik da sassaucin robobi, rage karyewar su, da kuma sauƙaƙa sarrafa su da siffanta robobi. Masu yin filastik gabaɗaya sune mahaɗan halitta masu tafasa sosai waɗanda ake iya haɗawa da resin, ba sa da guba, ba sa da wari, kuma suna dawwama ga haske da zafi. Waɗanda aka fi amfani da su sune esters na phthalate. Misali, a cikin samar da robobi na polyvinyl chloride, idan an ƙara ƙarin masu yin filastik, ana iya samun robobi masu laushi na polyvinyl chloride; idan an ƙara ko ƙasa da haka na filastik (adadin ƙasa da 10%), ana iya samun robobi masu ƙarfi na polyvinyl chloride.

4. Mai Daidaitawa Domin hana resin roba ya lalace kuma ya lalace ta hanyar haske da zafi yayin sarrafawa da amfani, da kuma tsawaita tsawon lokacin aiki, dole ne a ƙara mai daidaita sigina a cikin filastik. Abubuwan da aka fi amfani da su sune stearate da epoxy resin.

5. Masu launi Masu launi na iya yin robobi su sami launuka masu haske da kyau iri-iri. Rinjin halitta da aka saba amfani da su da kuma launuka marasa tsari a matsayin masu launi.

6. Man shafawa Aikin man shafawa shine hana filastik mannewa da ƙarfe yayin ƙera shi, kuma a lokaci guda yana sa saman filastik ya yi santsi da kyau. Man shafawa da ake amfani da su a yau da kullun sun haɗa da stearic acid da gishirin calcium da magnesium. Baya ga ƙarin abubuwan da ke sama, ana iya ƙara abubuwan hana harshen wuta, abubuwan kumfa, magungunan hana kumburi, da sauransu a cikin filastik.