Oligors na Musamman na Aiki

1.Magungunan Oligomers Biyu

Idan oligomer ya ƙunshi nau'ikan ƙungiyoyin aiki guda biyu daban-daban don warkarwa, kamar ƙungiyar acrylate wacce za a iya warkarwa ta free-radical, da kuma wani rukuni wanda za a iya warkarwa ta cationic photocuring, curing danshi, curing hydroxyl, ko thermal curing, to ana kiransa oligomer mai warkarwa ta biyu.

Ta amfani da bisphenol A epoxy resin da acrylic acid a cikin wani aikin esterification na zobe [epoxy group: carboxyl group = (1.5 ~ 2.0): 1, rabon molar], an shirya resin epoxy acrylate mai ɗauke da ƙungiyoyin epoxy. Ƙungiyoyin acrylic za su iya fuskantar polymerization na free-radical, yayin da ƙungiyoyin epoxy za su iya fuskantar photopolymerization na cationic ko warkar da zafi. Sakamakon bincike ya nuna cewa akwai hulɗar intramolecular tsakanin waɗannan ƙungiyoyin aiki guda biyu masu aiki, wanda zai iya haɓaka ci gaban photopolymerization na free-radical da cationic yadda ya kamata, yana inganta ƙimar amsawa da ƙimar juyawa ta ƙarshe, yayin da yake rage yawan hana iskar oxygen sosai. Fim ɗin da aka warke wanda oligomers masu maganin dual-cured suka samar yana nuna ingantattun kaddarorin injiniya.

Ta hanyar yin maganin hexamethylene diisocyanate tare da N,N-bis (3-aminopropyltriethoxysilane), sannan a yi maganin tare da hydroxyethyl acrylate, ana iya shirya polyurethane acrylate irin siloxane mai siffar siloxane mai siffar free-radical photocuring da kuma mai siffar danshi mai siffar dual-curing. Ana iya amfani da wannan a cikin fenti mai siffar photocuring.

Haɗa resin acrylate na phenolic epoxy wanda ke ɗauke da ƙungiyoyin epoxy yana haifar da kayan aiki tare da aikin gyaran hoto na free-radical da kuma gyaran zafi na dual-curing, wanda za'a iya amfani da shi a cikin juriyar solder mai iya ɗaukar hoto.

2.Masu Ƙirƙirar Kai na Oligomers

Akwai nau'ikan oligomers guda biyu tare da ayyukan farawa da kansu:

1. Oligomer ɗin kansa yana da ikon yin photoinitiating, don haka ƙarancin ko ma babu ƙarin photoinitiator da ake buƙata a cikin tsarin.
2. An haɗa ƙungiyar photoinitiating a cikin oligomer, yana mai da shi zuwa macromolecular photoinitiator wanda ke aiki duka a matsayin oligomer da kuma a matsayin photoinitiator a cikin tsarin.

Nau'in farko na oligomer mai fara kai shine sabon samfuri da kamfanin Amurka Ashland ya ƙirƙiro. Ana shirya shi ta hanyar haɗakar Michael tsakanin acrylate esters masu aiki da yawa da β-ketoesters (kamar ethyl acetoacetate, allyl acetoacetate, da 2-acetoacetoacetoxyethyl methacrylate). Carbon methylene mai aiki a cikin β-ketoester yana samar da sabon haɗin covalent tare da carbon na ƙarshe na haɗin carbon-carbon mai lamba biyu na acrylate. Ƙungiyar carbonyl a cikin β-ketoester tana da alaƙa da zaram ɗin carbon da aka maye gurbinsa gaba ɗaya. Wannan haɗin ba shi da ƙarfi a ƙarƙashin hasken ultraviolet. Bayan shan hasken UV, yana karyewa cikin sauƙi, yana samar da acetyl free radicals da wani macromolecular free radicals, ta haka yana samar da ikon fara kai.

Saboda haka, a cikin rufin UV, tawada, da manne da aka ƙera tare da oligomers masu farawa da kansu, ba a buƙatar ƙarin photoinitiator. Wannan yana guje wa matsaloli kamar wari, rawaya, wahalar haɗuwa, ruwan sama, ƙaura, da tsadar da ke tattare da ƙara photoinitiators na gargajiya.

Ana iya shirya oligomers masu fara kai ta hanyar halayen da ke tsakanin acrylate esters daban-daban da kuma masu ba da gudummawar Michael daban-daban, suna samar da jerin samfura.

Nau'ikan Acrylate sun haɗa da: acrylate, epoxy acrylate, polyurethane acrylate, polyester acrylate, silicone acrylate, melamine acrylate, perfluoroacrylate, fumarate, da maleate. Masu ba da gudummawar Michael sun haɗa da: β-ketoesters, β-diketones, β-ketoamides, β-ketoanilides, da sauransu. Ƙungiyar R' a cikin mai ba da gudummawar Michael na iya zama ƙungiya mai aiki ko ƙungiya mai warkarwa biyu.

Nau'i na biyu na oligomer mai farawa da kansa galibi ana shirya shi ne ta hanyar yin martani ga photoinitiators masu ɗauke da hydroxyl (kamar benzoin, 1173, 184, 2959) tare da oligomers waɗanda ke ɗauke da ƙungiyoyin isocyanate, ta haka ne ake ɗasa photoinitiator ɗin a kan oligomer don ƙirƙirar macromolecular photoinitiator tare da ƙungiyar farawa da aka gina a ciki.

Fa'idodin oligomers na photoinitiator da aka dasa:

1. Yawan ɗaukar hoto yana kusa da na oligomers na gargajiya tare da ƙananan ƙwayoyin photoinitiators.
2. Kyakkyawan jituwa da tsarin.
3. Yana rage ƙarfin ƙaura na mai fara ɗaukar hoto sosai.
4. Yana rage samar da samfuran lalatawar hasken rana daga mai kunna hasken rana (kamar benzaldehyde).
5. Mai kunna photoinitiator ba shi da guba kuma ba shi da lahani, wanda hakan ya sa ya dace a yi amfani da shi a cikin shafa da tawada don marufi na abinci.

Bayanai sun nuna cewa kayayyakin dashen sinadaran photoinitiators suna rage yawan ƙaura da kuma ƙarfin fitar da sinadarai daga cikin tarkacen masu farawa, kuma adadin benzaldehyde da aka samar a cikin fim ɗin da aka warke shi ma yana raguwa sosai. Saboda haka, dashen sinadaran photoinitiators a kan oligomers a zahiri yana haifar da nau'in masu samar da sinadarai na macromolecular waɗanda ba su da guba kuma ba su da lahani. Ana iya amfani da su a cikin shafa da tawada don marufi na abinci da magunguna. A cikin 2006, Hukumar Abinci da Magunguna ta Amurka (FDA) ta sanar da cewa ana iya amfani da murfin UV da tawada da aka samar ta amfani da marufi na macromolecular photoinitiators a cikin buga marufi na abinci da magunguna, wanda ya canza aikin da ya gabata inda ba za a iya amfani da tawada da murfin UV don marufi na abinci da magunguna ba, kuma ya buɗe sabon filin don amfani da tawada da murfin UV.

3.Ƙananan 'Yan Oligomers

A ƙarshen ƙarni na 20, wata sabuwar fasaha ta kayan da za a iya ɗaukar hoto - buga tawada ta UV - ta fito. Buga tawada hanya ce ta bugawa ba tare da taɓawa ba wacce ba ta buƙatar faranti na bugawa. Tana samar da hotuna ta hanyar fitar da digo na tawada a kan wani abu. Ta hanyar gyara zane-zane da rubutu ta kwamfuta da kuma sarrafa kan bugawa don fitar da digo na tawada daidai, tsari ne na ɗaukar hoto na dijital gaba ɗaya. A halin yanzu yana ɗaya daga cikin hanyoyin ɗaukar hoto na dijital mafi sauri, yana ba da fa'idodin bugawa akan buƙata, babban gudu, inganci, da launuka masu haske.

Babban abin da ake amfani da shi don buga inkjet na UV shine inkjet na UV, wanda ke buƙatar ink ɗin ya kasance yana da ƙarancin ɗanko, saurin warkarwa mai yawa, kwanciyar hankali mai kyau na launi, kuma babu lalata.