Ayini Ama-Coupling Agents kanye Nomsebenzi Wawo Oyisisekelo

 

 

Ayini Ama-Coupling Agents kanye Nomsebenzi Wawo Oyisisekelo

 

Ezimbonini zokumboza, uyinki, kanye nokunamathisela, ingabe uvame ukubhekana nalezi zinselele: ukumboza okusezindaweni zengilazi eziqhekeka ngemva kokubila, ukwehla okukhulu kwamandla okunamathela emikhiqizweni yethusi noma yesiliva ngemva kokuguga okushisa, noma ukuhlakazeka okungalingani lapho kufakwa ama-silane oketshezi ezimbozweni zempuphu?
Lezi zinkinga, ezingase zibonakale njengezimo "zokungalingani kwezinto ezibonakalayo," zivame ukubuyela emuva esithasiselweni esiyinhloko—i-coupling agent. Abaningi bakubona njengento "eyenza izinto zinamathele kangcono," kodwa empeleni "ixhumanisa" kanjani ezingeni lama-molecule? Kufanele ikhethwe kanjani ezinhlelweni ezahlukene, futhi yiziphi izingibe ezifihliwe ekusetshenzisweni kwayo?

 

Ngakho-ke, yini ngempelai-ejenti yokuxhumaI-ejenti yokuhlanganisa "ibhuloho lama-molecule" elikwazi ukusabela namaqembu asebenzayo ebusweni ezintweni ezingaphili (njengezinsimbi, ingilazi, noma izigcwalisi) ngenkathi futhi lakha izibopho zamakhemikhali noma ukuxhunyaniswa kwama-molecule nama-polymer e-organic (njenge-resins noma irabha). Umsebenzi walo oyinhloko ukuxazulula ingxabano eyisisekelo "yokungahambelani kwe-interface ye-inorganic-organic."

 

Ukuhlukaniswa Okuningiliziwe: Umklamo "Wemisebenzi Emibili" Wezisebenzi Zokuxhuma

Ukuze siqonde ama-coupling agents, kumele siqale siqaphele "abaphikisi" abakhuluma ngabo—ukuphikisana okukhona phakathi kwezinto ezingaphili kanye nama-polymers e-organic:

Izinto ezingaphili (izinsimbi, ingilazi, i-talc, i-fiberglass, njll.): Zine-polar ephezulu, zinamandla aphezulu ongaphezulu; izindawo ezizungezile zivame ukuba namaqembu e-hydroxyl (-OH) noma ama-orbital angenalutho (isb., ama-d-orbitals kuzinsimbi zokuguquka).

Ama-polymer e-organic (ama-epoxy resins, i-PU, ama-acrylic resins, i-PP, njll.): Athambile, anezinhlayiya zama-molecule eziguquguqukayo; ikakhulukazi izakhiwo ezingezona eziphansi noma eziphansi, okwenza kube nzima ukubopha okuzinzile nezinto ezingaphili.

Umklamo wesakhiwo sama-coupling agents wenzelwe "ukubamba izinhlangothi zombili," oqukethe ama-terminal "asebenza kabili".

 

I-One End "Anchors" Isigaba Esingaphili: Ukuhlangana Kwamakhemikhali Nezindawo Ezingaphili

Uma sibheka ama-silane coupling agents asetshenziswa kakhulu njengesibonelo, ukuphela kwawo okungaphili ngokuvamile kuqukethe amaqembu e-alkoxy angafakwa amanzi (-Si-OR, lapho i-R iyi-methyl, i-ethyl, njll.):

I-Hydrolysis: Uma kukhona amanzi noma umswakama, i--Si-OR iyayi-hydrolyzes ukuze yakhe amaqembu e-silanol (-Si-OH).

Ukuminyana: Amaqembu e-silanol adlula ekuminyaneni kwamanzi kanye namaqembu e-hydroxyl ebusweni bezinto ezingaphili (isb., -Si-OH engilazini, -M-OH kuma-oxide ensimbi), akha izibopho eziqinile ze-covalent (-Si-O-Si- noma -Si-OM-). Lokhu "kubethela" ngempumelelo i-coupling agent ebusweni obungaphili.

Ama-silane acwebezelayo ensimbi athatha lesi sinyathelo esiqhubekayo: ukubhekana nenselele yokuba khona kweqembu le-hydroxyl eliphansi ezindaweni ezifana nethusi, isiliva, noma i-nickel, izakhiwo ze-heterocyclic kuma-molecule azo (aqukethe ama-athomu afana ne-nitrogen noma i-sulfur) zingakha "izibopho zokuxhumanisa" ngama-orbital ensimbi angenalutho. Angase adale ngisho "izakhiwo ze-chelating" ezizinzile ezinamalungu amahlanu noma ayisithupha - lezi zibopho zinamandla kunezibopho ze-covalent ezivamile, zinqoba inselele yemboni yokunamathela kabi kwama-silane endabuko kuma-substrate ethusi.

 

Esinye Isiphetho "Sihlangana" Nesigaba Se-Organic: Ukubopha Okuqinile Ne-Resin

Isiphelo se-organic se-coupling agent siphethe amaqembu asebenzayo aklanyelwe ukusabela ne-resin, eklanyelwe uhlobo oluthile lwe-resin:

Izinhlelo ze-Epoxy: Zihlonyiswe ngamaqembu e-epoxy, zingabamba iqhaza ngqo ekuqineni nasekuhlanganiseni ama-resin e-epoxy.

Izinhlelo ze-UV: Ezinezibopho ezimbili, zingasabela ngaphansi kokukhanya kwe-UV ngezinhlelo zama-free radical noma ze-cationic.

Izinhlelo ze-PU: Ngamaqembu e-amino noma e-isocyanate, zingasabela ne-isocyanate (NCO) ukuze zakhe ukuxhumana kwe-urea.

Izinhlelo ze-Thermoplastic (PP/PE): Zihlanganisa amaketanga amade e-alkyl noma amaqembu e-maleic anhydride, zihlangana ne-resin ngokusebenzisa ukuxinana kwama-molecule (isb., ama-titanate coupling agents).

 

I-ejenti Yokuxhumanisa ≠ I-Surfactant ≠ I-Dispersant

Lezi zinhlobo ezintathu zezithasiselo zivame ukudideka, kodwa umehluko oyinhloko ulele ekutheni zakha yini izibopho zamakhemikhali:

I-Surfactant: Ithuthukisa ukumanzika kwe-interfacial ngokusebenzisa amaqembu e-hydrophilic-lipophilic; akukho zibopho zamakhemikhali ezakhekayo, okwenza kube lula ukufuduka nokwehluleka.

Isihlanzisi: Sivimbela ukuhlangana kwezakhi ngokuxosha ishaja noma ukuvinjelwa kwe-steric; ikakhulukazi kuncike ekusebenzisaneni ngokomzimba.

I-Coupling Agent: Yakha izibopho zamakhemikhali ezixhumanisa izigaba ze-inorganic kanye ne-organic, esebenza njengebhuloho "elihlala njalo" lokuxhumana. Ayigcini nje ngokusabalalisa ama-filler kodwa futhi ithuthukisa amandla okuxhumana kanye nokuqina.

Ishekeamakhasi ewebhuukuthola imikhiqizo eyengeziwe. Ukuze uthole imininingwane eyengeziwe, sicelaXhumana nathi.