The field performance of wood modified with 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) is reported after outdoor exposure above ground (UC3), in ground (UC4) and in the marine environment (UC5) at six different sites in Europe and Australia. Results from more than seven years field testing with respect to the DMDHEU treatment level, wood species (Scots pine, European beech, spotted gum and slash pine) and climate conditions were evaluated. DMDHEU was shown to significantly improve the biological durability of Scots pine sapwood after exposure under UC3, UC4 and UC5 conditions, which confirmed previous findings on the laboratory scale. The latter was classified as ‘durable to very durable’ (durability class DC1-2). However, DMDHEU modification seemed to be more efficient in Scots pine, slash pine and spotted gum so that higher chemical loadings are required for European beech to reach similar resistance against wood-destroying fungi. Under feeding pressure of Teredo navalis, DMDHEU treatment was graded as ‘durable’.
AlfredsenG, BrischkeC, Meyer-VeltrupL, HumarM, FlætePO.2017. The effect of different test methods on durability classification on modified wood. Pro Ligno. 13:290–297.
2.
AugustaU.2007. Untersuchung der natürlichen Dauerhaftigkeit wirtschaftlich bedeutender Holzarten bei verschiedener Beanspruchung im Außenbereich [dissertation]. Hamburg: University of Hamburg.
3.
AWPA (American Wood Protection Association) E7. 2015. Standard field test for evaluation of wood preservatives to be used in ground contact (UC4A, UC4B, UC4C); Stake test.
4.
BartholmeM.2005. Eigenschaften von Spanplatten aus DMDHEU-modifizierten Spänen [master's thesis]. Goettingen: University of Goettingen, Faculty of Forest Sciences and Forest Ecology.
5.
BollmusS.2011. Biologische und technologische Eigenschaften von Buchenholz nach einer Modifizierung mit 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) [dissertation], Goettingen: University of Goettingen, Faculty of Forest Sciences and Forest Ecology.
6.
BreuerAK.2008. Optimierung eines Heißdampftrocknungsprozesses für Holzvernetzung mit Buche [master's thesis]. Goettingen: University of Goettingen, Faculty of Forest Sciences and Forest Ecology.
7.
BrischkeC, GellerichA, MilitzH, StarckM.2017. Performance of coated and uncoated horizontal lap-joint members during 20 years of outddor exposure. Wood Res. 62:883–894.
8.
BrischkeC, OlberdingS, MeyerL, BornemannT, WelzbacherCR.2013. Intrasite variability of fungal decay on wood exposed in ground contact. Int Wood Prod J. 4:37–45. doi: 10.1179/2042645312Y.0000000014
9.
BrischkeC., SelterV.2019. Mapping the decay hazard of wooden structures in topographically divergent regions. In: FredrikssonM., editor. Proceedings of the 15th Annual Meeting of the Northern European Network for wood Science and Engineering – WSE2019. Lund: Northern European Network for Wood Science and Engineering; p. 98–100.
10.
Dieste MärklA.2009. Wood-water relationships in wood modified with 1,3-dimethylol-4,5-dihydroxy ethylene urea (DMDHEU) [dissertation]. Goettingen: Faculty of Forest Sciences and Forest Ecology, University of Goettingen.
11.
EmmerichL.2016. Holzmodifizierung von Kiefer (Pinus sylvestris L.) mit DMDHEU und modifizierten DMDHEU-Varianten im Vergleich [master's thesis]. Goettingen: Faculty of Forest Sciences and Forest Ecology, University of Goettingen.
12.
EmmerichL, BollmusS, MilitzH.2019a. Wood modification with DMDHEU (1.3-dimethylol-4.5-dihydroxyethyleneurea) - State of the art, recent research activities and future perspectives. Wood Mat Sci Eng. 14:3–18. doi: 10.1080/17480272.2017.1417907
13.
EmmerichL, MilitzH, BrischkeC.2018. Long-term performance of DMDHEU-treated wood exposed in ground, above ground and in the marine environment. Johannesburg: The International Research Group on Wood Preservation: IRG/WP. 18–40825.
14.
EmmerichL, StrohbuschS, BrischkeC, BollmusS, MilitzH.2019b. Study on the ability of wood-destroying fungi to grow through chemically modified wood. Quebec: The International Research Group on Wood Preservation: IRG/WP. 19–40858.
15.
EN 252. 2015. Field test method for determining the relative protective effectiveness of a wood preservative in ground contact. Brussels: CEN (European Committee for Standardization).
16.
EN 275. 1992. Wood preservatives; determination of the protective effectiveness against marine borers. Brussels: CEN (European Committee for Standardization).
17.
EN 350. 2016. Durability of wood and wood-based products – testing and classification of the durability to biological agents of wood and wood-based materials. Brussels: CEN (European Committee for Standardization).
18.
HillCAS.2006. Wood modification – chemical, thermal and other processes. West Sussex: Wiley.
19.
KlüppelA, CraggSM, MilitzH, MaiC.2015. Resistance of modified wood to marine borers. Int Biodeterior Biodegrad. 104:8–14. doi: 10.1016/j.ibiod.2015.05.013
20.
KlüppelA., MilitzH., MaiC.2012. Resistance of modified wood to the common shipworm (Teredo navalis) as assessed by marine trial. In: JonesD., MilitzH., PetričM., PohlevenF., HumarM, PavličM., editors. Proceedings of the 6th European conference on wood modification. Ljubljana: European Conference on Wood Modification; p. 239–242.
21.
KrauseA.2006. Holzmodifizierung mit N-Methylolvernetzern [dissertation]. Goettingen: Faculty of Forest Sciences and Forest Ecology, University of Goettingen.
22.
KrauseA, HofC, MilitzH.2004. Novel wood modification processes for window and cladding products. Ljubljana: The International Research Group on Wood Preservation, IRG/WP/04-40285.
23.
MaiC.2010. Review: Prozess der chemischen Holzmodifizierung – Stand der industriellen Entwicklung. Holztechnologie. 51:21–26.
24.
Meyer-VeltrupL, BrischkeC, KällanderB.2017. Testing the durability of timber above ground: evaluation of different test methods. Eur J Wood Wood Prod. 75:291–304. doi: 10.1007/s00107-016-1137-8
25.
MeyerL, BrischkeC, MelcherE, BrandtK, LenzMT, SoetbeerA.2014. Durability of English oak (Quercus robur L.) – comparison of decay progress and resistance under various laboratory and field conditions. Int Biodeterior Biodegrad. 86:79–85. doi: 10.1016/j.ibiod.2013.06.025
26.
MilitzH.1993. Treatment of timber with water soluble dimethylol resins to improve their dimensional stability and durability. Wood Sci Technol. 27:347–355. doi: 10.1007/BF00192221
27.
MilitzH, NortonJ.2013. Performance testing of DMDHEU-modified wood in Australia. Stockholm: The International Research Group on Wood Preservation: IRG/WP 13-30613.
28.
PetersenHA.1983. Cross-linking with formaldehyde-containing reactants. In: LewinM., SelloS.B., editors. Hand book of fibre science and technology, Volume II: chemical processing of fibers and fabrics – functional finishes – part A. New York: Marcel Dekker; p. 47–327.
29.
PfefferA, KrauseA, MilitzH.2008. Testing modified wood and natural durability in use class 3 with the block-test approach. In: Peek R.D., van Acker, J., editors. Socio-economic perspectives of treated wood for the common European market – Sustainability through new technologies for enhanced wood durability. Proceedings of the final conference of COST Action E37, Bordeaux, France, 29–30 September 2008; p. 77–84.
30.
RitschkoffAC, RättöM, NurmiA, KokkoH, RappA, MilitzH.1999. Effect of some resin treatments on fungal degradation reactions. Rosenheim: The International Research Group on Wood Preservation, IRG/WP/99-10318.
31.
SchaffertS.2006. Steuerung und Optimierung von Holzvernetzungsprozessen [dissertation]. Goettingen: Faculty of Forest Sciences and Forest Ecology, University of Goettingen.
32.
SchindlerWD, HauserPJ.2004. Chemical finishing of textiles. Cambridge: Woodhead Publishing Ltd.
33.
ScholzG, KrauseA, MilitzH.2010. Exploratory study on the impregnation of Scots pine sapwood (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) with different hot melting waxes. Wood Sci Technol. 44:379–388. doi: 10.1007/s00226-010-0353-3
34.
SchultzTP, GoodellB, NicholasDD. editors 2014. Deterioration and protection of sustainable biomaterials. American Chemical Society. Washington (DC): Oxford University Press.
35.
StirlingR, AlfredsenG, BrischkeC, De WindtI, FrancisLP, Frühwald HanssonE, HumarM, JermerJ, KlamerM, KutnikM, 2016. Global survey on durability variation – on the effect of the reference species. Lisbon: The International Research Group on Wood Preservation, IRG/WP/16-20573.
36.
TondiG, ThévenonMF, MiesB, StandfestG, PetutschniggA, WielandS.2013. Impregnation of Scots pine and beech with tannin solutions: effect of viscosity and wood anatomy in wood infiltration. Wood Sci Technol. 47:615–626. doi: 10.1007/s00226-012-0524-5
37.
Van AckerJ, NurmiA, GrayS, MilitzH, HillCAS, KokkoH, RappA.1999. Decay resistance of resin treated wood. Rosenheim: The International Research Group on Wood Preservation, IRG/WP/99-30206.
38.
VermaP, JungaU, MilitzH, MaiC.2009. Protection mechanisms of DMDHEU treated wood against white and brown rot fungi. Holzforschung. 63:371–378. doi: 10.1515/HF.2009.051
39.
VidelovCL.1989. Biological degradation resistance of pine wood treated with dimethylol compounds. Lappeenranta: The International Research Group on Wood Preservation, IRG/WP/89-3528.
40.
WepnerF.2006. Entwicklung eines Modifizierungsverfahrens für Buchenfurniere (Fagus sylvatica L.) auf basis von zyklischen N-Methylol-Verbindungen [dissertation]. Goettingen: Faculty of Forest Sciences and Forest Ecology, University of Goettingen.
41.
XieY, KrauseA, MilitzH.2014. Wood protection with dimethyloldihydroxy-ethyleneurea and its derivatives. In: SchultzT. P., GoodellB., NicholasB. B, editors. Deterioration and protection of sustainable biomaterials – ACS Symposium Series. Washington, DC: Oxford University Press; p. 287–299.
