Nkwakọ ngwaahịa ihe ọmụma - Kedu ihe na-ebute mgbanwe agba nke ngwaahịa plastik?

• Mbibi oxidative nke akụrụngwa nwere ike ime ka ọ gbanwee mgbe ị na-akpụzi na okpomọkụ dị elu;
• Mgbanwe nke agba agba na okpomọkụ dị elu ga-eme ka nchọpụta nke ngwaahịa plastik;
• Mmeghachi omume kemịkalụ n'etiti ụcha agba na akụrụngwa ma ọ bụ ihe mgbakwunye ga-eme ka agbapụta agba;
• Mmeghachi omume n'etiti mgbakwunye na akpaaka oxidation nke mgbakwunye ga-eme ka mgbanwe agba;
• Tautomerization nke agba agba n'okpuru omume nke ọkụ na okpomọkụ ga-eme ka mgbanwe agba nke ngwaahịa;
• Ihe mmetọ ikuku nwere ike ime mgbanwe na ngwaahịa rọba.

1. Ihe kpatara Plastic Molding

1) Nbibi nke oxidative nke akụrụngwa nwere ike ime ka ọ gbanwee mgbe ị na-akpụzi na okpomọkụ dị elu

Mgbe mgbanaka na-ekpo ọkụ ma ọ bụ efere ọkụ nke ihe na-emepụta ihe na-emepụta plastik na-adị mgbe niile na ọnọdụ okpomọkụ n'ihi njikwa, ọ dị mfe ime ka ọnọdụ okpomọkụ dị n'ógbè ahụ dịkwuo elu, nke na-eme ka ihe ọkụkụ na-eme ka ọ ghara ịdị na-ekpo ọkụ ma na-agbaze na okpomọkụ dị elu. Maka plastik ndị ahụ na-ekpo ọkụ na-ekpo ọkụ, dị ka PVC, ọ dị mfe mgbe ihe a na-eme, mgbe ọ dị njọ, ọ ga-ere ọkụ ma gbanwee edo edo, ma ọ bụ ọbụna oji, tinyere nnukwu ego nke obere molecular volatiles na-ejupụta.

Nbibi a gụnyere mmeghachi omume dịkadepolymerization, random yinye scission, mwepụ nke akụkụ dị iche iche na obere molekul arọ bekee.

• Depolymerization

Mmeghachi omume nbibi na-eme na njikọ njikọ ọnụ, na-eme ka njikọ ahụ daa n'otu n'otu, na monomer emepụtara na-agbanwe ngwa ngwa. N'oge a, ịdị arọ molekụla na-agbanwe nke ukwuu nke ukwuu, dị ka usoro ntụgharị nke yinye polymerization. Dị ka ikpochapụ ọkụ nke methyl methacrylate.

• Ọkpụkpọ Random Scission (mmebi)

Amarakwa dị ka nkwụsịtụ ma ọ bụ agbụ agbajiri enweghị usoro. N'okpuru ọrụ nke ike igwe, radieshon ike dị elu, ebili mmiri ultrasonic ma ọ bụ reagent nke kemịkalụ, ụdọ polymer na-agbaji na-enweghị ebe a kapịrị ọnụ iji mepụta polymer dị ala. Ọ bụ otu n'ime ụzọ nke mmebi polymer. Mgbe yinye polymer na-agbada n'enweghị usoro, ịdị arọ nke molekụla na-agbada ngwa ngwa, na ọnwụ nke polymer dị ntakịrị. Dịka ọmụmaatụ, usoro mmebi nke polyethylene, polyene na polystyrene na-abụkarị mmebi nke enweghị usoro.

Mgbe a na-akpụzi polymer dị ka PE na oke okpomọkụ, ọnọdụ ọ bụla nke agbụ isi nwere ike ịgbaji, na ịdị arọ molekụla na-agbada ngwa ngwa, mana mkpụrụ monomer dị obere. A na-akpọ ụdị mmeghachi omume a, nke a na-akpọ scission na-enweghị usoro, mgbe ụfọdụ a na-akpọ mmebi, polyethylene The free radicals kpụrụ mgbe yinye scission na-arụsi ọrụ ike, gbara ya gburugburu karịa nke abụọ hydrogen, na-enwekarị mmeghachi omume mbufe yinye, ọ fọrọ nke nta ka ọ bụrụ na ọ dịghị monomers na-emepụta.

• Mwepụ nke ndị nnọchi anya

PVC, PVAc, wdg nwere ike nweta mmeghachi omume mwepụ n'ọnọdụ mgbanwe mgbe a na-ekpo ọkụ, ya mere ala dị larịị na-apụtakarị n'usoro thermogravimetric. Mgbe polyvinyl chloride, polyvinyl acetate, polyacrylonitrile, polyvinyl fluoride, wdg na-ekpo ọkụ, a ga-ewepụ ihe ndị nọchiri anya ya. N'iji polyvinyl chloride (PVC) dịka ọmụmaatụ, a na-edozi PVC na okpomọkụ dị n'okpuru 180 ~ 200 ° C, ma na okpomọkụ dị ala (dị ka 100 ~ 120 ° C), ọ na-amalite dehydrogenate (HCl), ma na-efunahụ HCl nke ukwuu. ngwa ngwa na gburugburu 200 Celsius. Ya mere, n'oge nhazi (180-200 ° C), polymer na-eme ka ọ bụrụ ọchịchịrị na agba na ike dị ala.

HCl efu nwere mmetụta catalytic na dehydrochlorination, na chloride metal, dị ka ferric chloride nke emere site na omume nke hydrogen chloride na akụrụngwa nhazi, na-akwalite catalysis.

Pasent ole na ole nke acid absorbent, dị ka barium stearate, organotin, lead compound, wdg, ga-agbakwunyere na PVC n'oge nhazi okpomọkụ iji meziwanye nkwụsi ike ya.

Mgbe a na-eji eriri nkwurịta okwu na-eme ka eriri nkwurịta okwu na-agba agba, ọ bụrụ na oyi akwa polyolefin na waya ọla kọpa adịghị eguzosi ike, a ga-emepụta carboxylate na-acha akwụkwọ ndụ akwụkwọ ndụ na polymer-ọla kọpa interface. Mmeghachi omume ndị a na-akwalite mgbasa nke ọla kọpa n'ime polymer, na-eme ka oxidation catalytic nke ọla kọpa ngwa ngwa.

Ya mere, iji belata ọnụ ọgụgụ mmebi oxidative nke polyolefins, a na-agbakwunye phenolic ma ọ bụ aromatic amine antioxidants (AH) iji kwụsị mmeghachi omume dị n'elu wee mepụta free radicals A·: ROO·+AH-→ROOH+A·

• Mmebi oxidative

Ngwaahịa polymer ekpughere n'ikuku na-etinye oxygen ma na-enweta oxidation iji mepụta hydroperoxides, na-aga n'ihu na-emepụta ebe a na-arụ ọrụ, na-emepụta radicals free, wee na-enweta mmeghachi omume radical free (ie, auto-oxidation process). A na-ekpughere ndị polymer na ikuku oxygen na ikuku n'oge nhazi na ojiji, na mgbe a na-ekpo ọkụ, mmebi oxidative na-eme ngwa ngwa.

Thermal oxidation nke polyolefins bụ nke free radical chain mmeghachi omume mmeghachi omume, nke nwere autocatalytic omume na ike kewara n'ime atọ nzọụkwụ: mmalite, ibu na nchupu.

Mgbochi agbụ nke otu hydroperoxide kpatara na-eduga na mbelata nke ịdị arọ molekụla, na ngwaahịa ndị bụ isi nke scission bụ alcohols, aldehydes, na ketones, bụ ndị na-emecha oxidized na carboxylic acid. Carboxylic acid na-ekere òkè dị ukwuu na oxidation catalytic nke ọla. Nbibi oxidative bụ isi ihe kpatara mmebi nke anụ ahụ na akụrụngwa nke ngwaahịa polymer. Nbibi oxidative na-adịgasị iche na nhazi molekul nke polymer. Ọnụnọ nke ikuku oxygen nwekwara ike ime ka mmebi nke ìhè, okpomọkụ, radieshon na ike arụ ọrụ na polymers, na-eme ka mmeghachi omume mmebi dị mgbagwoju anya. A na-agbakwunye Antioxidants na polymers iji belata mmebi oxidative.

2) Mgbe a na-edozi plastik ma na-akpụzi ya, agba agba na-emebi emebi, na-ada ma na-agbanwe agba n'ihi enweghị ike iguzogide oke okpomọkụ.

Pigmenti ma ọ bụ ihe eji esiji eme ihe maka agba rọba nwere oke okpomọkụ. Mgbe a ruru oke okpomọkụ, pigmenti ma ọ bụ ihe e ji esiji ákwà ga-enwe mgbanwe kemịkal iji mepụta ogige dị arọ dị ala dị iche iche, usoro mmeghachi omume ha dịkwa mgbagwoju anya; pigmenti dị iche iche nwere mmeghachi omume dị iche iche. Na ngwaahịa, iguzogide okpomọkụ nke pigmenti dị iche iche nwere ike ịnwale site na usoro nyocha dị ka ọnwụ dị arọ.

2. Colorants na-emeghachi omume na akụrụngwa akụrụngwa

A na-egosipụta mmeghachi omume n'etiti ndị na-acha agba na ihe ndị dị ndụ na nhazi nke ụfọdụ pigmenti ma ọ bụ ihe eji esiji ákwà na ihe ndị dị ndụ. Mmeghachi omume kemịkalụ ndị a ga-eduga na mgbanwe na hue na mmebi nke polymers, si otú ahụ gbanwee njirimara nke ngwaahịa rọba.

• Mbelata mmeghachi omume

Ụfọdụ polymers dị elu, dị ka naịlọn na aminoplasts, bụ ihe ndị na-ebelata acid siri ike na steeti a wụrụ awụ, nke nwere ike ibelata ma mee ka pigmenti ma ọ bụ ihe na-esiji eme ihe na-eguzosi ike na nhazi okpomọkụ.

• Mgbanwe alkaline

Alkaline ụwa ọla na PVC emulsion polymers ma ọ bụ ụfọdụ stabilized polypropylenes nwere ike "base mgbanwe" na alkaline ụwa ọla na colorants ịgbanwe agba si-acha anụnụ anụnụ-acha ọbara ọbara na oroma.

PVC emulsion polima bụ usoro nke VC na-polymerized site na-akpali akpali na emulsifier (dị ka sodium dodecylsulfonate C12H25SO3Na) aqueous ngwọta. Mmeghachi omume nwere Na +; iji meziwanye okpomọkụ na ikuku oxygen nke PP, 1010, DLTDP, wdg na-agbakwunyekarị. Oxygen, antioxidant 1010 bụ mmeghachi omume transesterification catalyzed site na 3,5-di-tert-butyl-4-hydroxypropionate methyl ester na sodium pentaerythritol, na DLTDP na-akwado ya site na-azaghachi Na2S aqueous ngwọta na acrylonitrile Propionitrile bụ hydrolyzed iji mepụta thiodipropionitrile. enwetara site na esterification na mmanya lauryl. Mmeghachi omume ahụ nwekwara Na+.

N'oge a na-akpụzi na nhazi nke ngwaahịa rọba, ihe fọdụrụ Na+ na akụrụngwa ga-emeghachi omume na pigmenti ọdọ nwere ion metal dị ka CIPigment Red48: 2 (BBC ma ọ bụ 2BP): XCa2 ++ 2Na+ → XNa2+ + Ca2+

• Mmeghachi omume n'etiti pigments na hydrogen Halides (HX)

Mgbe okpomọkụ na-ebili na 170 Celsius ma ọ bụ n'okpuru ọrụ ọkụ, PVC na-ewepụ HCI iji mepụta njikọ abụọ jikọtara ọnụ.

Halogen nwere ire ọkụ na-egbochi polyolefin ma ọ bụ ngwaahịa rọba na-acha ọkụ na-acha ọkụ na-ekpochapụkwa HX mgbe a na-akpụzi ya na oke okpomọkụ.

1) Ultramarine na HX mmeghachi omume

Acha anụnụ anụnụ Ultramarine a na-ejikarị na agba rọba ma ọ bụ na-ewepụ ìhè edo edo, bụ ngwakọta sọlfọ.

2) Ọla kọpa ntụ ntụ ntụ ntụ na-eme ka oxidative ire ere nke akụrụngwa PVC

Enwere ike oxidized pigmenti ọla kọpa na Cu + na Cu2 + na oke okpomọkụ, nke ga-eme ka ire PVC dịkwuo elu.

3) Mbibi nke ion ígwè na polymers

Ụfọdụ pigmenti nwere mmetụta na-ebibi ihe na polymers. Dịka ọmụmaatụ, ọdọ mmiri manganese pigmenti CIPigmentRed48: 4 adịghị mma maka ịkpụzi ngwaahịa plastik PP. Ihe kpatara ya bụ na ion manganese dị iche iche na-agbanwe agbanwe na-eme ka hydroperoxide na-ebufe electrons na oxidation thermal ma ọ bụ photooxidation nke PP. Mwepu nke PP na-eduga n'ịka nká ngwa ngwa nke PP; njikọ ester na polycarbonate dị mfe iji mee ka hydrolyzed na-emebi emebi mgbe ọ na-ekpo ọkụ, na mgbe e nwere ions ígwè na pigmenti, ọ dị mfe ịkwalite ire ere; ion metal ga-akwalitekwa ire ere ọkụ-oxygen nke PVC na akụrụngwa ndị ọzọ, ma mee mgbanwe agba.

N'ịchịkọta, mgbe ị na-emepụta ngwaahịa plastik, ọ bụ ụzọ kachasị mma ma dị irè iji zere iji pigmenti na-acha agba agba na-emeghachi omume na akụrụngwa.

3. Mmeghachi omume n'etiti colorants na mgbakwunye

1) Mmeghachi omume n'etiti sọlfọ nwere pigmenti na mgbakwunye

Sulfur nwere pigmenti, dị ka cadmium odo (ihe ngwọta siri ike nke CdS na CdSe), adịghị mma maka PVC n'ihi adịghị ike acid na-eguzogide, na e kwesịghị iji ihe mgbakwunye nwere ndu.

2) Mmeghachi omume nke ogige nwere ndu nwere sọlfọ nwere stabilizers

Ọdịnaya ndu na chrome yellow pigment ma ọ bụ molybdenum red na-emeghachi omume na antioxidants dị ka thiodistearate DSTDP.

3) Mmeghachi omume n'etiti pigmenti na antioxidant

Maka akụrụngwa nwere antioxidants, dị ka PP, ụfọdụ pigmenti ga-emeghachi omume na antioxidants, si otú ahụ na-ebelata ọrụ nke antioxidants na ime ka ikuku oxygen kwụsie ike nke akụrụngwa ka njọ. Dị ka ọmụmaatụ, phenolic antioxidants na-adị mfe na-etinye obi gị dum site na carbon ojii ma ọ bụ meghachi omume na ha ka ha kwụsị ọrụ ha; phenolic antioxidants na titanium ion na ngwaahịa rọba na-acha ọcha ma ọ bụ na-acha ọkụ na-etolite ogige phenolic aromatic hydrocarbon iji mee ka ngwaahịa na-acha odo odo. Họrọ antioxidant kwesịrị ekwesị ma ọ bụ tinye mgbakwunye inyeaka, dị ka nnu zinc anti-acid (zinc stearate) ma ọ bụ P2 ụdị phosphite iji gbochie mwepu nke pigmenti ọcha (TiO2).

4) Mmeghachi omume n'etiti pigmenti na ìhè stabilizer

Mmetụta nke pigmenti na ìhè stabilizers, ma e wezụga mmeghachi omume nke sọlfọ-nwere pigments na nickel-nwere ìhè stabilizers dị ka akọwara n'elu, n'ozuzu ebelata irè nke ìhè stabilizers, karịsịa mmetụta nke egbochiri amine ìhè stabilizers na azo odo na red pigments. Mmetụta nke ọdịda kwụsiri ike na-apụta ìhè karịa, ọ naghịkwa eguzosi ike dị ka enweghị agba. Enweghị nkọwa doro anya maka ihe a.

4. Mmeghachi omume n'etiti ihe mgbakwunye

Ọ bụrụ na ejiri ọtụtụ ihe mgbakwunye eme ihe na-ekwesịghị ekwesị, mmeghachi omume a na-atụghị anya ya nwere ike ime na ngwaahịa ahụ ga-agbanwe agba. Dịka ọmụmaatụ, Sb2O3 na-egbochi ire ọkụ na-emeghachi omume na sọlfọ nwere anti-oxidant iji mepụta Sb2S3: Sb2O3+-S–→Sb2S3+-O-

Ya mere, a ghaghị ịkpachara anya na nhọrọ nke mgbakwunye mgbe ị na-atụle usoro mmepụta.

5. Auxiliary Auto-oxidation na-akpata

Ngwakọta oxidation akpaka nke phenolic stabilizers bụ ihe dị mkpa iji kwalite ngbanwe nke ngwaahịa na-acha ọcha ma ọ bụ ọkụ. A na-akpọkarị ngbanwe a "Pinking" na mba ndị ọzọ.

A na-ejikọta ya na ngwaahịa oxidation dị ka BHT antioxidants (2-6-di-tert-butyl-4-methylphenol), ma na-eme ka 3,3′,5,5′-stilbene quinone ìhè mmeghachi omume mmeghachi omume na-acha ọbara ọbara. naanị na ọnụnọ oxygen na mmiri na enweghị ìhè. Mgbe ekpughere ya na ọkụ ultraviolet, ọkụ na-acha uhie uhie stilbene quinone na-aghọ ngwa ngwa ka ọ bụrụ ngwaahịa nwere otu mgbanaka edo edo.

6. Tautomerization nke agba agba n'okpuru Action nke ìhè na okpomọkụ

Ụfọdụ acha pigments na-enweta tautomerization nke nhazi molecular n'okpuru omume nke ìhè na okpomọkụ, dị ka iji CIPig.R2 (BBC) pigmenti na-agbanwe site na azo ụdị na quinone, nke na-agbanwe mmetụta mbụ conjugation mmetụta na-eme ka e guzobe conjugated agbụ. . ibelata, na-ebute mgbanwe agba site na acha anụnụ anụnụ-acha uhie uhie na-acha anụnụ anụnụ gaa na ìhè oroma-acha ọbara ọbara.

N'otu oge ahụ, n'okpuru catalysis nke ìhè, ọ decomposes na mmiri, na-agbanwe co-crystal mmiri na-eme ka ọ daa.

7. Ihe kpatara ikuku ikuku

Mgbe a na-echekwa ma ọ bụ jiri ngwaahịa plastik mee ihe, ụfọdụ ihe na-emeghachi omume, ma ọ bụ akụrụngwa, ihe mgbakwunye, ma ọ bụ pigmenti agba, ga-emeghachi omume na mmiri dị na ikuku ma ọ bụ mmetọ kemịkalụ dị ka acid na alkalis n'okpuru omume nke ọkụ na okpomọkụ. A na-ebute mmeghachi omume kemịkalụ dị mgbagwoju anya dị iche iche, nke ga-eduga n'ịkụda ma ọ bụ mwepu ka oge na-aga.

Enwere ike zere ma ọ bụ belata ọnọdụ a site n'ịgbakwụnye ikuku oxygen stabilizers kwesịrị ekwesị, ihe nkwụnye ọkụ, ma ọ bụ ịhọrọ ihe mgbakwunye ihu igwe dị elu na pigmenti.