He polymer i hoʻohana nui ʻia ka Polypropylene i hoʻohana ʻia ma nā ʻano hana like ʻole ma muli o kona hui maikaʻi loa o nā waiwai. Hiki ke hoʻonui hou ʻia kona mau waiwai, e like me ke kino, ka mīkini a me ka optical me ka hoʻohana kūpono ʻana i nā mea hoʻohui nucleating a me nā mea hoʻomālamalama. Kōkua kēia mau mea hoʻohui i ka crystallization o PP i ka wā o ka hana ʻana, no laila e hoʻonui ana i nā waiwai i loaʻa mua.

E hoʻomaopopo pehea e hoʻohana ai i nā mea hoʻohuihui a me nā mea hoʻomālamalama a me nā ʻōlelo aʻoaʻo koho e hoʻonui pono i ka wikiwiki o ka hana ʻana, hoʻololi i ke ʻano a me ke ʻano, a hōʻemi i ka noe i kāu mau ʻano polypropylene.

I. Ke kuleana o nā mea hoʻomālamalama nucleating ma PP

ʻO ke kristalinitas o nā polymers semi-crystalline ke kuleana no nā ʻano he nui, e like me ke kūpaʻa o ka dimensional, ka mōakāka, a me ka paʻakikī.

No kahi ʻāpana a me ke kaʻina hana i ho'ākāka ʻia, hoʻomalu ʻia ka crystallinity e ke ʻano polymer, ke ʻano hana, a me nā kūlana hana e hopena ai i kahi kaulike kikoʻī o ka hōʻiliʻili ʻana o ka wela a me ka hoʻomaʻalili ʻana. No laila, he ʻokoʻa pinepine ka crystallinity, ʻokoʻa ka mōʻaukala wela no ka ʻili a me ke kikowaena o nā ʻāpana a i ʻole nā ​​​​waiwai.

Hoʻolalelale a hoʻoponopono nā mea hoʻohui nucleating a me nā clarifiers i ka crystallization e ʻae ana e hoʻoponopono i nā waiwai hope o nā polymers semi-crystalline i nā koi hana.

·I loko o nā ʻano polypropylene, ʻo ka hoʻohui ʻana i nā mea hoʻohuihui (i kapa ʻia hoʻi he nucleators) e hopena i ka hoʻomaikaʻi ʻana i ka hana a me nā waiwai hana, e like me:

· Hoʻomaikaʻi ʻia ka mālamalama a me ka hoʻemi ʻana i ka noe

· Hoʻonui i ka ikaika a me ke kūpaʻa

· Hoʻomaikaʻi ʻia ka Mahana Hoʻololi Wela (HDT)

· Hoʻemi ʻia ka manawa pōʻaiapuni

· Hoʻemi ʻia ke kaua ʻana a me ka emi ʻana o ka like ʻana

· Hoʻemi ʻia ka ʻike pigment e pili ana i nā loli waiwai me nā kala like ʻole

· Hoʻomaikaʻi ʻia ke kaʻina hana ma kekahi mau noi

No laila, ʻo ka nucleation kahi ala ikaika e hoʻomaikaʻi ai i nā waiwai kino, mechanical, a me optical o ka polypropylene. Hiki ke hoʻomaikaʻi ʻia ka maopopo, ka paʻa dimensional, warpage, shrinkage, CLTE, HDT, nā waiwai mechanical a me ka hopena pale ma ke koho akahele ʻana o nā nucleators a i ʻole clarifiers.

II. ʻO Polypropylene a me kona ʻano kristal

He polymer crystalline i hoʻohana nui ʻia ʻo Polypropylene, he polymer waiwai i hana ʻia mai ka polymerization o ka propene monomer. Ma hope o ka polymerization, hiki iā PP ke hana i ʻekolu mau ʻano kaulahao kumu (atactic, isotactic, syndiotactic) ma muli o ke kūlana o nā hui methyl. Hōʻike ʻia ka crystallinity o ka polymer e:

· Nā ʻano a me nā nui o nā kristal

· ʻO nā lakio crystallinity, a ma ka hopena

· Ke kuhikuhi ʻana o nā kristal

He polymer semi-crystalline ka polypropylene Isotactic (iPP). Hōʻike ʻia ia e kahi lakio kumukūʻai-hana maikaʻi loa, e lilo ia i mea hoihoi loa i nā ʻano hana like ʻole e like me ke kaʻa, nā mīkini, nā paipu, ka hoʻopili ʻana, a pēlā aku.

Ua pili pono ka helu kuhikuhi isotacticity o iPP i ke kiʻekiʻe o ka crystallinity nona ka hopena nui i ka hana polymer. Hoʻonui ka isotacticity i nā kinetics crystallization, flexural modulus, paʻakikī a me ka transparency, a hoʻemi i ke kūpaʻa hopena a me ka permeability.

Hoʻohālikelike ka papa ma lalo i nā waiwai o ʻelua homopolymers polypropylene me kahi helu isotacticity ʻokoʻa.

III. Ka hoʻoheheʻe ʻia ʻana o ka Polypropylene
Ma muli o nā kūlana, hiki i ka Isotactic Polypropylene ke hoʻopili i ʻehā mau pae like ʻole i hōʻike ʻia he α, β, γ a me ka mesomorphic smectic. ʻO nā pae α a me β ka mea nui loa.

Pae α

1. ʻOi aku ka paʻa o kēia pae a ʻike nui ʻia.

2. No kēia mau kristal ka ʻōnaehana kristal monoclinic.

Pae β

1. He metastable kēia pae, a no ka ʻōnaehana kristal pseudo-hexagonal kona mau kristal.

2. Loaʻa ka pae β i loko o ka polypropylene i hoʻopili ʻia me ka poloka a hiki ke hana ʻia ma ka hoʻohui ʻana i nā mea hoʻohuihui kikoʻī.

3. Ua ʻike ʻia kēia ʻano kristal e Padden lāua ʻo Keith i ka makahiki 1953; hiki ke hoʻolaha ʻia e ka crystallization ma waena o 130°C a me 132°C, ke kuhikuhi ʻoki kiʻekiʻe, a i ʻole ka hoʻohui ʻana o nā mea hoʻohuihui kikoʻī.

4. ʻO ka loaʻa ʻana o ka pae β i loko o nā homopolymers polypropylene e hoʻomaikaʻi pinepine i ka ductility o ka huahana i hoʻopau ʻia, a ʻo ka hopena ka mea nui loa ke hiki ka ʻike pae β i 65%.

Pae γ

1. He metastable nō hoʻi kēia pae, me nā kristal triclinic.

2. He mea kākaʻikahi kēia ʻano kristal; ʻike nui ʻia ia ma ka polypropylene kaumaha molekala haʻahaʻa a ua hoʻokumu ʻia e ka crystallization ma lalo o ke kaomi kiʻekiʻe loa a me nā helu hoʻomaʻalili haʻahaʻa loa.

Ⅳ. Ke Kaʻina Hana Nucleation ma Polypropylene

Ua ʻike maopopo ʻia ʻo ke kumu hoʻomaka o ka crystallization o nā polymers he mau germs liʻiliʻi (nā ʻāpana liʻiliʻi) i hoʻokomo maoli ʻia i loko o nā koena catalyst e like me ka heheʻe, nā haumia, ka lepo, a me nā mea ʻē aʻe. A laila hiki ke hoʻololi a kāohi i ke ʻano crystalline ma ka hoʻohui ʻana i nā germs "artificial" i hoʻokomo ʻia i loko o ka polymer heheʻe. Ua kapa ʻia kēia hana ʻo Nucleation.

Hoʻohana ʻia nā nucleators a i ʻole nā ​​​​mea hoʻohui nucleating e hāʻawi i nā wahi no ka hoʻomaka ʻana o nā kristal.

ʻO nā clarifiers kahi ʻohana liʻiliʻi o nā nucleators e hāʻawi ana i nā crystallites liʻiliʻi e hoʻopuehu ana i ka mālamalama liʻiliʻi a, ma muli o ka hopena, hoʻonui i ka maopopo no ka mānoanoa like o ka paia o kahi ʻāpana.

ʻO ke kuleana o kēia mau mea hoʻohuihui, ʻo ia ka hoʻomaikaʻi ʻana i nā waiwai kino a me nā ʻano mechanical o nā ʻāpana i pau.

Ⅴ. Nā Nucleators a me nā Clarifiers: He Panel Waiwai o nā Additives

Nā mea hoʻohuihui ʻāpana

ʻO nā mea hoʻoheheʻe nucleating particulate/nucleants he mau hui hoʻoheheʻe kiʻekiʻe ia i hoʻopuehu ʻia i loko o ka polymer melt ma o ka compounding. Hana kēia mau ʻāpana ma ke ʻano he 'point nuclei' ʻokoʻa kahi e hoʻomaka ai ka ulu ʻana o ka kristal polymer.

ʻO ke kiʻekiʻe o ka nui o nā nuclei e alakaʻi ai i ka crystallization wikiwiki (nā manawa pōʻaiapuni pōkole), a me nā pae kiʻekiʻe o ka crystallinity, kahi e hoʻomaikaʻi ai i ka ikaika, ka ʻoʻoleʻa, a me ka HDT o ka PP.

ʻO ka liʻiliʻi o nā hōʻiliʻili kristal (spherulites) e alakaʻi ai i ka emi ʻana o ka hoʻopuehu ʻana o ka mālamalama a me ka hoʻomaikaʻi ʻana i ka moakāka.

ʻO nā mea hoʻohuihui particulate i hoʻohana pinepine ʻia e komo pū me nā paʻakai a me nā minelala, e like me ka talc, sodium benzoate, phosphate esters a me nā paʻakai organik ʻē aʻe.

Ua manaʻo ʻia ʻo Talc a me ka sodium benzoate he mau nucleants hana haʻahaʻa, haʻahaʻa ke kumukūʻai, a hāʻawi i kahi hoʻomaikaʻi iki i ka ikaika, ka ʻoʻoleʻa, HDT, a me ka manawa pōʻaiapuni.

ʻO nā nucleants hana kiʻekiʻe a me ke kumukūʻai kiʻekiʻe, e like me nā phosphate esters a me nā paʻakai bicycloheptane e hāʻawi i nā waiwai kino maikaʻi aʻe a me kekahi hoʻomaikaʻi ʻana i ka mōakāka.

Nā mea hoʻoheheʻe nucleus hiki ke hoʻoheheʻe ʻia

ʻO nā mea hoʻoheheʻe nucleating hiki ke hoʻoheheʻe ʻia, i kapa ʻia hoʻi ʻo 'melt-sensitive', he haʻahaʻa ko lākou mau kiko heheʻe a hoʻoheheʻe ʻia i loko o ka PP heheʻe.

I ka hoʻomaʻalili ʻana o ka polymer heheʻe i loko o ka ʻōmole, hoʻopuka mua kēia mau nucleants e hana ana i kahi pūnaewele i hoʻolaha maikaʻi ʻia me ka ʻilikai kiʻekiʻe loa.

I ka hoʻomau ʻana o ka mahana e hāʻule, hana nā fibrils e pili ana i kēia pūnaewele ma ke ʻano he nuclei e hoʻomaka ai i ka crystallization polymer.

ʻO ke kiʻekiʻe loa o ka nui o nā nuclei e alakaʻi ai i nā hōʻiliʻili kristal PP liʻiliʻi loa, ka mea e hāʻawi ai i ka pae haʻahaʻa loa o ka hoʻopuehu ʻana o ka mālamalama a me ka mōakāka maikaʻi loa.

He mau nucleants nā mea hoʻomālamalama a pau, akā, ʻaʻole maikaʻi nā nucleants a pau.

ʻO kekahi mau nucleants maʻamau, e like me ka sodium benzoate a me ka talc, ʻaʻole e hōʻemi i ka nui o ka spherulite ma kahi nui e hāʻawi i kahi haʻahaʻa haʻahaʻa a me ka ʻāpana i hoʻoheheʻe ʻia me ka maopopo kiʻekiʻe. Loaʻa ka maopopo maikaʻi loa i ka wā e hoʻohana ʻia ai nā nucleants soluble.

ʻO nā mea hoʻoheheʻe organik hiki ke hoʻoheheʻe ʻia e hana ma ke ʻano he mau mea hoʻomālamalama e komo pū me nā sorbitols, nonotols, a me nā trisamides.

ʻOiai ua hoʻohana nui ʻia kēia mau nucleants e hoʻokō i ka mōakāka kiʻekiʻe a me ka noe haʻahaʻa, hoʻomaikaʻi pū lākou i nā waiwai kino a hoʻemi i ka manawa pōʻaiapuni.

ʻAno o ka ʻāpana a me ka lakio ʻano

Hiki i nā ʻāpana nucleant me nā ʻano nila (e like me ADK STAB NA-11) ke alakaʻi i nā waiwai shrinkage like ʻole i ka mīkini a me nā kuhikuhi transverse. Hiki i kēia anisotropy shrinkage ke alakaʻi i ka warpage ma ka ʻāpana hope loa. Hiki i nā ʻāpana nucleant me kahi geometry planer ke hāʻawi i ka shrinkage like ʻoi aku ma nā ʻaoʻao ʻelua e alakaʻi ana i ka warpage liʻiliʻi.

Ka nui o ka ʻāpana a me ka hoʻolaha ʻana o ka nui o ka ʻāpana

ʻO ka liʻiliʻi o ka nui o nā ʻāpana e alakaʻi ai i ka hoʻomaikaʻi ʻana i ka nucleation, akā hiki i nā ʻāpana liʻiliʻi ke paʻakikī ke hoʻopuehu. ʻO kekahi mau ʻāpana nucleant, e like me ka sodium benzoate, e hōʻuluʻulu hou.

Mea Hoʻohana ʻia no ka ʻAkika Scavenger

Hiki i kekahi mau mea hoʻopau waikawa, e like me nā paʻakai waikawa momona (e laʻa me ka calcium stearate) ke kūʻē i kekahi mau nucleants, e like me nā phosphate esters a me ka sodium benzoate. Pono e hoʻohana ʻia ʻo Dihydrotalcite me kēia mau nucleants.

Mai hoʻohana i ka calcium stearate me ka sodium benzoate no ka mea e hoʻopau loa ka calcium stearate i ka nucleation o ka sodium benzoate.

Ke kēkelē o ka hoʻopuehu ʻana a me ke alo o nā Agglomerates i hoʻopuehu ʻole ʻia

Hoʻohui pinepine ʻo Sodium benzoate i nā agglomerates a paʻakikī ke hoʻopuehu pono.

Mahana Hoʻoheheʻe

Pono nā Sorbitols i nā mahana hoʻoheheʻe kiʻekiʻe e hāʻawi i ka mōakāka maikaʻi loa, ʻoiai pono lākou e hoʻoheheʻe piha ʻia i loko o ka polymer melt.

Nā Synergies a me nā Antagonisms ma waena o nā Nucleants a me nā Additives ʻē aʻe

Hiki i nā mea ʻokiʻoki waikawa ke synergistic a antagonistic paha. Hoʻopilikia maikaʻi ʻole nā ​​paʻakai waikawa momona i ka modulus o ka phosphate ester nucleated PP.

Koho i ka ʻākauNā Nucleantsa me nā mea hoʻomālamalama no PP

Ma mua o ke koho ʻana i ka mea hoʻohuihui a wehewehe paha kūpono no kāu noi PP, e hoʻoholo i ka hoʻomaikaʻi waiwai āu e makemake nui ai:

a.Inā he mea nui ka noe haʻahaʻa a me ka mōakāka kiʻekiʻe, a laila koho i kekahi o nā mea hoʻomālamalama hiki ke hoʻoheheʻe ʻia.

b.No nā koi moakāka haʻahaʻa, ʻo kanā esters phosphatehiki ke hoʻohana ʻia.

c.Inā ʻo ke modulus kiʻekiʻe ka mea nui loa, a laila koho i kekahi o nā esters phosphate.

d.Inā ʻo ke kumukūʻai haʻahaʻa ka mea nui loa, a laila koho i ka sodium benzoate.

e.Inā he mea nui ka haʻahaʻa o ka warpage a me ka haʻahaʻa o ka pigment sensitivity, a laila koho i ka paʻakai bicycloheptane.

He mea nui hoʻi e hoʻoholo pehea e hoʻokomo ʻia ai ka nucleant i loko o ka resin PP. E hana mau i nā hoʻokolohua kūpono e hōʻoia i ka hoʻokō ʻia ʻana o ka hoʻolaha maikaʻi a me ka nucleation.

E holo i ka DSC ma ka resin PP nucleated. ʻO ka hoʻomaikaʻi ʻana i ka manawa pōʻaiapuni e pili pinepine me ka piʻi ʻana o ka mahana crystallization (Tc). E hoʻāʻo i nā waiwai o ka specimen i hoʻoheheʻe ʻia.

Inā makemake ʻoe e nīnau e pili ana i nā huahana e pili ana i nā mea hoʻohui nucleating, e ʻoluʻolu e leka uila maikāhea iā mā˚oui kēlā me kēia manawa.