Voronezh, Voronezh, Russian Federation
Voronezh, Voronezh, Russian Federation
One of the main indicators of the quality of plywood is its environmental friendliness, which is characterized by the content of free formaldehyde. To produce plywood with formaldehyde emission class E0, E1, low-toxic urea-formaldehyde resins should be used. These resins have low final viscosity, which can lead to a decrease in the strength properties of plywood due to excessive penetration of glue into the wood. The viscosity of the working solution of the glue can be changed by the use of fillers (wood flour, rye flour, kaolin, etc.). The results of the research have showed that wood flour has high adsorption capacity and 2-5 m. shares of wood flour increase the viscosity of the adhesive from 60 to 180 s by the VZ-4 viscometer. At the same time, a large amount of grinding dust accumulates in the woodworking shops. To assess the possibility of using grinding dust as a filler of urea-formaldehyde resins, a comparative analysis of the properties of grinding dust obtained by grinding various materials and wood flour in accordance with State Standard 16362-86 has been carried out. The results have showed that grinding dust is comparable to wood flour in moisture, bulk density. The fractional composition of the grinding dust is larger, but most of it corresponds to the necessary fractions of 0.25; 0.18; 0.125 after sorting. The article studies the effect of the fraction and the amount of grinding dust on the strength properties of plywood, as well as on the technological properties of the adhesive (dynamic viscosity, pH, gel time). The maximum increase in the strength of plywood has been 63% when using grinding dust of 0.125 fractions in the amount of 1 m.sh. Adding grinding dust to the adhesive solution leads to an increase in its dynamic viscosity and the larger the particle, the more the viscosity changes. Filling of urea-formaldehyde resins with grinding dust shifts the pH of the adhesive solution towards the neutral and slightly acidic medium and reduces the gelatin time to 55-60 sec. The conducted studies show that the use of grinding dust as a filler of urea-formaldehyde adhesives leads to a decrease in internal stresses in the cured adhesive and an increase in the strength of the gluing of plywood
plywood, strength, filler, grinding dust, viscosity
1. Biryukov, V. G. Tehnologiya kleenyh materialov i drevesnyh plit [Tekst] : ucheb. posobie / V. G. Vasechkin. - M. : MGUL, 2012. - 292 s.
2. GOST 16361 - 87. Muka drevesnaya. Tehnicheskie usloviya [Tekst]. - Vzamen GOST 16361 - 79; vved. 1989 - 01 - 01. - M.: Izdatel'stvo standartov, 1988. - 7 s.
3. GOST 16362 - 86. Muka drevesnaya. Metody ispytaniy [Tekst]. - Vzamen GOST 16362 - 79; vved. 1988 - 01 - 01. - M.: IPK Izdatel'stvo standartov, 1999. - 11 s.
4. Kantieva E.V. Issledovanie vozmozhnosti ispol'zovaniya shlifoval'noy pyli, poluchennoy na razlichnom oborudovanii, v kachestve napolnitelya karbamidoformal'degidnyh kleev [Tekst] / E.V. Kantieva, L.V. Ponomarenko, A.R. Fazliahmetova // Aktual'nye napravleniya nauchnyh issledovaniy XXI veka: teoriya i praktika : sbornik nauchnyh trudov po materialam mezhdunarodnoy zaochnoy nauchno-prakticheskoy konferencii. - Voronezh, 2017. - T. 5. № 1 (27). - S. 42-46.
5. Kulikov, V. A. Tehnologiya kleenyh materialov i plit [Tekst] : dop. M-vom vyssh. i sred. spec. obrazova-niya SSSR v kachestve ucheb. dlya studentov vuzov, obuchayuschihsya po special'nosti "Tehnologiya derevoobrabotki" / V. A. Kulikov, A. B. Chubov ; V. A. Kulikov, A. B. Chubov. - M. : Lesn. prom-st', 1984. - 344 s.
6. Murzin V.S. Effektivnost' primeneniya napolniteley pri proizvodstve fanery na malotoksichnyh kar-bamidoformal'degidnyh smolah [Tekst] / V.S. Murzin, E.V. Kantieva, L.V. Ponomarenko // Lesotehnicheskiy zhur-nal. - 2012. - № 3. - S. 20-24.
7. Murzin V.S. Issledovanie vozmozhnosti primeneniya shlifoval'noy pyli v kachestve napolnitelya karba-midoformal'degidnyh kleev pri proizvodstve fanery [Tekst] / V.S. Murzin, T.L. Ischenko, L.V. Ponomarenko, E.V. Kantieva, O.V. Lavlinskaya // Lesotehnicheskiy zhurnal. - 2012. - № 4. - S. 14-18.
8. Pat. 2456586 RF, MPK G01N27/22. Sposob opredeleniya vnutrennih napryazheniy [Tekst] / V. M. Popov, A. V. Ivanov, A. P. Novikov, M. A. Shendrikov, A. V. Latynin ; patentoobladatel' GOU VPO "VGLTA". - № 2011109552/28 ; zayavl. 14.03.2011 ; opubl. 20.07.2012, Byul. № 20. - 5 s.
9. Snegireva S.N. Izmenenie struktury drevesiny berezy posle povrezhdeniya pozharom [Tekst] / S.N. Sne-gireva // Lesotehnicheskiy zhurnal. - 2012. - № 4. - S. 68-71
10. Clemons, C. Wood-plastic composites in the United States: The interfacing of two industries / C. Clemons // For. Prod. - № 10. - 2002. - 52 p.
11. Experimental study on flexural behavior of glulam and laminated veneer lumber beams / Liu, W. Q. Yang, H. F. Dong, F. Q.,[et al.] // Modern bamboo structures: Conference: 1st International Conference on Modern Bamboo Structures Location: Hunan Univ, Changsha, PEOPLES R CHINA Date: OCT 28-30, 2007. - 2008. - P. 159-16
12. Kol H.S., Keskin H., Korkut S., Akbulut T. Laminated veneer lumber from Rowan (Sorbusaucuparia-Lipsky). African journal of agricultural research. OCT 2009, pp. 1101-1105.
13. Li, HY.,Li, CC..Gao, Q.,Zhang, SF., Li, JZ. Properties of soybean-flour-based adhesives enhanced by attapulgite and glycerol polyglycidyl ether / Industrial crops and products //HY. Li, CC. Li, Q. Gao, SF. Zhang, JZ. Li. - AUG 2014. - P. 35-40.
14. Liu W.Q. Yang H.F. Dong F.Q. [et al.] Experimental study on flexural behavior of glulam and laminated veneer lumber beams. Moernbamboo structures: Conference: 1st International Conference on Modern Bamboo Struc-tures Loca-tion: Hunan Univ, Changsha, PEOPLES R CHINA Date: OCT 28-30, 2007, 2008, pp. 159-169.
15. Maderthaner, W. A. und J. B. Verbestel. Formaldehydarme Spanplatten durch Gasbehandlung. Ein Verfahren zur Verringerung der Formaldehydabgabe fertiggepresster Holzwerkstoffplatten. [Text] / W. A. Maderthaner und J. B. Verbestel. // Holz-Zentralblatt 107. - 1980. - pp. 1917-1918.
