Adhesives da tsarin haɗin su

 Manne da ake amfani da shi don manne itace dole ne ya kasance mai ƙarfi a cikin ruwa, mai jure kamuwa da cututtukan fungal kuma dole ne ya sami ƙarfin haɗin gwiwa da suka kafa. Dole ne wannan ƙarfin ya haura zuwa iyakar ƙarfin juzu'i na itacen da ake mannawa.

Bisa ga asalinsu, adhesives sun kasu kashi uku:

1. dabba, wanda aka yi daga sunadarai na asalin dabba (madara, jini, kasusuwa da fata daga dabbobi) Wannan rukuni ya hada da kashi (tvutkalo), fata, albumin da casein;
2. na ganye, wanda aka yi daga sitaci da sunadaran shuka (kwayoyin wake, vetiver, yisti waken soya, tsaba sunflower, da sauransu). Wannan rukunin kuma ya ƙunshi sitaci glue,
3.  roba, samu chemically daga phenol, formaldehyde da carbamide.

Adhesives sun kasu kashi-kashi mai ƙarfi a cikin ruwa, barga a cikin ruwa da rashin kwanciyar hankali a cikin ruwa. Adhesives masu juriya sosai a cikin ruwa suna jure aikin ruwa tare da zafin jiki na 100^oC ba tare da babban raguwa a cikin ƙarfin mannewa ba (phenol-formaldehyde adhesives). Adhesives masu jure ruwa a ƙarƙashin rinjayar ruwa tare da zafin jiki na 18 zuwa 20^oC gabaɗaya baya rage ƙarfin mannewa sosai (rea resins da albumin adhesives). Adhesives maras ƙarfi a cikin ruwa suna rasa ƙarfin mannewa a ƙarƙashin rinjayar ruwa (kashi, fata, casein-ammonia).
Hakanan an raba mannewa zuwa thermoreactive ko wanda ba za a iya jurewa ba da thermoplastic ko mai juyawa. Adhesives na thermoreactive suna juya ƙarƙashin rinjayar zafin jiki zuwa wani abu mai wuya, wanda ba zai iya narkewa kuma ba zai iya jurewa ba (carbamide da melarnine resin). A ƙarƙashin rinjayar zafi, thermoplastic adhesives narke, kuma bayan sanyaya sun taurare kuma ba sa canza yanayin sinadarai (kashi da fata). Ana amfani da adhesives na thermoplastic, musamman manne kafinta da mannen fata. Don samar da plywood mai jure ruwa, ana amfani da adhesives na thermoreactive.
An ƙaddara ingancin manne kafinta ta hanyar solubility, wettability, kumburi, colloidity, ikon kumfa, taurare, putrefy, ƙarfin haɗin gwiwa da ƙarfin mannewa.
Solubility na manne yana ƙaddara ta yanayin zafin ruwa. A yanayin zafi ƙasa da 25^oC manne ba ya narke. Saboda haka, kumburin busassun tabarmi a cikin tayal da tabarmi da aka yi da sikelin kifi za a iya aiwatar da shi ne kawai a zafin jiki sama da 25.^oC. Sama da 70 - 80^oC baya buƙatar zafi kullu.
Yanayin zafi na ji bai kamata ya wuce 15 - 17% ba, saboda haka ya kamata a adana shi a bushe, wurare masu kyau. Ji da zafi sama da 20% cikin sauri ya lalace (rube) kuma ya rasa ikon tsayawa. An ƙayyade abun ciki na ɓangaren litattafan almara kamar yadda danshi na itace.
Gilashin kafinta yana da hygroscopic sosai. Yana iya ɗaukar nauyinsa sau 10-15 a cikin ruwa. Hanyar yin ta ta dogara ne akan wannan siffa ta tutkal. Titkalo a cikin tayal, sanya shi a cikin ruwa mai tsabta, ana zuba shi da ruwan zãfi a zazzabi na 25 - 30. ^oC kuma ana adana shi don 10-12 hours. A wannan lokacin, kullu yana ɗaukar iyakar adadin ruwan da ake buƙata don shirye-shiryensa. Ana sanya wannan nama mai kumbura a cikin wani jirgin ruwa mai ƙasa biyu kuma yana mai zafi zuwa zafin jiki na 70 - 80. ^oC. Idan kumfa mai yawa ya fito a saman yayin dumama, ya kamata a dafa kullu na tsawon minti 5-10 sannan a cire kumfa. Duk da haka, bai kamata a bar kullu ya tafasa ba, saboda yana rasa danko da mannewa.
Rubewa (rubewa) yana ɗaya daga cikin munanan halaye na ɓangaren litattafan almara na itace. Don haka, kullu da aka shirya ya kamata a kiyaye shi a zazzabi na 5-10 ^oC don kada ya lalace. Ɗaya daga cikin mahimman kaddarorin kullin kafinta shine ikonsa na canzawa zuwa yanayin hoto. Kakin zuma mai girma yana shiga cikin yanayin hoto a yanayin zafi mafi girma fiye da kakin zuma mai ƙarancin hankali. Saƙa masu kyau suna canzawa da rauni ko kaɗan zuwa yanayin hoto. Irin wannan manne ba su dace da ingancin gluing na itace ba. Mahimman kayan da aka narkar da manne, mai mannewa, ya dogara da matakin maida hankali. An ƙaddara matakin ƙaddamarwa ta hanyar adadin ruwa a cikin maganin manne.
Halin daɗaɗɗen shinge na daidaitattun bututun gwaji yana ƙayyade ingancin haɗin katako. Idan aka yi shelar a kan itacen, to, ingancin mannewa shi ne mafi kyau, idan a kan itacen da a saƙa ne, ingancin ya fi muni, kuma mafi muni shi ne idan an yi shi a kan saƙar da kanta.
Bugu da ƙari ga ingancin ji da kuma mannewa, yanayin gluing yana da tasiri mai girma akan ƙarfin katako na katako. A cikin tebur. 1, ana ba da hanyoyin daidaitawa na haɗin gwiwa.

Tebur 1: Yanayin gluing tare da mannen kafinta

A cikin dakin da ake yin gluing, zafin jiki bai kamata ya zama ƙasa da 25 ba^oC. Ya kamata a nisantar da zane-zane da zanen iska mai sanyi da injinan aikin katako masu saurin gaske ke haifar da su. Rage yawan zafin jiki na saman da za a liƙa na iya haifar da raguwar ƙarfin haɗin haɗin gwiwa.

Preheating abubuwan da za a manna suna inganta aikin gluing.

Juriya na daidaitaccen maganin manne akan lalata (mildew) a 25^oC shine kwanaki hudu don mafi kyawun nau'in saƙar kashi, kwana uku don nau'ikan I, II da III. Juriya na daidaitaccen maganin ƙwayar fata shine kwana hudu da kwana uku don mafi kyawun nau'in I, kwanaki biyar don nau'in II - kwana hudu, da kwanaki biyar don nau'in III a zazzabi na 25.^o.

Ƙarfin ƙarfin ƙarfi na samfuran manne shine 100 kg / cm don saƙa na fata, don mafi kyau kuma don nau'in farko.², don nau'in II 75 kg/cm² kuma ga nau'in III 60
kg / cm² . Don nama na kasusuwa, iyakar ƙarfin ƙarfi na samfuran manne shine 90 kg / cm don mafi kyawun nau'in², don nau'in farko 80 kg / cm², don nau'in II 55 da nau'in III 45 kg / cm².

Foda casein manne shi ne cakuda casein, slaked lemun tsami, ma'adinai salts (sodium fluoride, soda, jan karfe sulfate, da dai sauransu) da kuma man fetur. Ana amfani da shi don manna abubuwa na katako, itace da yadudduka, kwali, da dai sauransu. Dangane da ingancin kayan asali da kuma hanyar samarwa, akwai nau'ikan manne casein guda biyu: kari (B-107) da talakawa (OB).

Dole ne wannan manne ya kasance yana da kamannin foda mai kama da juna ba tare da ƙazanta na waje ba, kwari, tsutsa da burbushin mold kuma kada ya wari ruɓe. Lokacin hada kashi 1 bisa nauyin wannan manne da kashi 2,1 ta nauyin ruwa a cikin sa'a daya a zazzabi na 15 - 20^oC an samo bayani mai kama da juna, wanda ba ya ƙunshi lumps kuma wanda ya dace da gluing.

Lokacin gluing injiniyoyin gine-gine, waɗanda ke aiki a cikin yanayin ƙananan bambance-bambancen zafin jiki da ƙarancin zafi, alamar siminti na Portland mai lamba 400 (har zuwa 75% na nauyin foda) ana ƙara shi zuwa wannan manne don ƙara juriya ga ruwa da rage farashinsa. Don manne na casein, ƙarfinsa na mannewa yana da mahimmanci, wato, lokacin da yake riƙe da mannewa, wanda ya dace da aiki mai amfani. Bayan sa'o'i 24, maganin wannan manne, karin nau'in, ya kamata ya kasance da bayyanar wani nau'i na pictium na roba, maganin nau'in nau'in OB manne ya kamata ya sami aiki mai aiki na akalla sa'o'i 4 tun lokacin da aka haxa shi da ruwa.

Iyakar ƙarfin haɗin haɗin ash da itacen oak yakamata ya zama aƙalla 100 kg/cm² don nau'in manne karin, lokacin da aka gwada shi a cikin bushe, 70 kg / cm² - bayan sa'o'i 24 na nutsewa cikin ruwa; don nau'in OB - 70 kg / cm² lokacin da aka gwada a cikin bushewa da 50 kg / cm² bayan awa 24 na nutsewa cikin ruwa. Ana yin gwajin alamun ingancin wannan manne a cikin dakunan gwaje-gwaje.

Lokacin gluing tare da manne na casein, matsa lamba a cikin latsawa ya bambanta daga 2 zuwa 15 kg / cm.² bisa ga nau'in aikin da ake nufi da kashi.

Lokacin da wannan manne ya ƙunshi dutse ko soda, bai kamata a yi amfani da shi don manna nau'ikan itacen da ke da tannin a cikin abun da ke ciki ba, kamar su. Oak.

Roba adhesives ne gaba daya jure ruwa. Ana amfani da adhesives mai sanyi na phenol-formaldehyde nau'in KB - 3 da B - 3. B - 3 ya ƙunshi sassa 10 na resin B, sashi na bakin ciki da sassa 2 na filler.

An shirya adhesives na phenolformaldehyde kamar haka: ana sanya resin B a cikin ƙayyadadden adadin a cikin tukunyar mahaɗar gwangwani inda ake kiyaye zafin jiki a 15 - 20^oC, sa'an nan kuma ana ƙara diluent kuma a haxa shi a hankali har sai an sami nau'i mai kama da juna. Bayan haka, ana ƙara filler curing kuma a gauraye na minti 10-15. Ya kamata a adana manne da aka yi ta wannan hanyar a cikin firiji, wanda a zahiri jirgin ruwa ne wanda ruwan gudu ke wucewa.
Don gluing itace, ana kuma amfani da mannen carbamide, babban abin da ke cikinsa shine resin carbamide, wanda aka samo daga carbamide na roba da formaldehyde. Lokacin gluing tare da waɗannan manne, itace dole ne ya sami matsakaicin danshi na 12%.
Daga cikin fitsari-formaldehyde glues, K-7 manne ya kamata a haskaka, wanda ya ƙunshi MF-17 resin, hardener, 10% oxalic acid bayani (daga 7,5 zuwa 14 sassa da nauyi) da kuma itace gari filler.