Adhesion interaction of one-component polyurethane in cross-laminating southern pine wood treated with micronized copper azole—type C (MCA-C)

Abstract Copper remains one of the key biocides for protecting timber in soil contact. Historically, copper-based preservatives relied on solubilized copper. Over the past decade, micronized copper systems have largely replaced soluble copper systems in this application. While micronized copper chemistries have been shown to perform well over time with reduced copper leaching compared to solubilized copper, data are lacking on the effects of repeated leaching cycles on resistance of the timber to fungal attack. The potential effects of repeated leaching cycles of micronized copper azole–treated southern pine (Pinus spp.) blocks on both copper losses and resistance to fungal attack were explored over 20 leaching cycles using Gloeophyllum trabeum and Rhodonia placenta as test fungi. Copper losses during leaching were elevated for the first two cycles and steadily declined with additional cycling. There were no noticeable differences in fungal-associated weight losses in blocks exposed to G. trabeum. There was only a slight increase in average block weight losses with R. placenta, although blocks exposed to this fungus experienced higher weight losses with increased leaching cycles. The results suggest that repeated leaching exposures may produce some localized increases in susceptibility to fungal attack, but the overall effects were minor.

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Using Fourier Transform Near-Infrared Spectroscopy to Predict the Mechanical Properties of Thermally Modified Southern Pine Wood

Applied Spectroscopy ◽

10.1177/0003702816644453 ◽

2016 ◽

Vol 70 (10) ◽

pp. 1676-1684

Author(s):

Li Tong ◽

Wenbo Zhang

Keyword(s):

Mechanical Properties ◽

Near Infrared ◽

Nir Spectroscopy ◽

Modulus Of Rupture ◽

Coefficient Of Determination ◽

Southern Pine ◽

Pine Wood ◽

Close Relationship ◽

Thermally Modified Wood ◽

Modified Wood

This study seeks to estimate the mechanical properties of thermally modified wood (TMW) using near-infrared (NIR) spectroscopy to measure 80 samples in three-point bending tests. Near-infrared spectra collected from the transverse, radial, and tangential sections of wood, coupled with chemometric techniques, were used to predict the mechanical properties of southern pine wood, from which NIR models were constructed based on partial least squares and corresponding cross-validation. The coefficient of determination between NIR transverse section spectra, as well as two mechanical properties of wood samples, modulus of rupture (MOR) and modulus of elasticity (MOE), were above 0.92 and greater than values for other sections. Spectral data from the transverse sections were richer than data from other sections, and thus, a model based on transverse sections better predicts the mechanical properties of wood. A close relationship between the values for mechanical properties (MOE and MOR) and the NIR spectra of thermally modified southern pine wood can be demonstrated, which provides the potential to predict the mechanical properties of untreated and thermally modified wood.

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Speciation of arsenic and chromium in the leachate from chromated copper arsenate (CCA) type C treated southern pine (Pinus spp.)

Holzforschung ◽

10.1515/hf.2005.031 ◽

2005 ◽

Vol 59 (2) ◽

pp. 199-204 ◽

Cited By ~ 1

Author(s):

Weining Cui ◽

Lisveth Flores del Pino ◽

Thomas C. Voice ◽

Karen Chou ◽

D. Pascal Kamdem

Keyword(s):

Treated Wood ◽

Chromated Copper Arsenate ◽

Exchange Chromatography ◽

Southern Pine ◽

Total Chromium ◽

Flame Atomic Absorption Spectroscopy ◽

Flame Atomic Absorption ◽

Type C ◽

Pinus Spp ◽

Copper Arsenate

Abstract A 558-h laboratory leaching test (AWPA E-11) was carried out on both commercially and laboratory chromated copper arsenate (CCA) type C-treated southern pine. Arsenic, chromium, and copper concentrations in the leachate collected were examined. Leaching of chromium and copper from CCA-treated wood cubes were nearly undetectable using flame atomic absorption spectroscopy after 174 and 366 h, respectively. Less than 10% of the total chromium in the leachate was present as hexavalent chromium [Cr(VI)] after leaching for 30 h. Selective ion-exchange chromatography was used to speciate arsenic in the leachate. In the first 270 h, approximately 70–90% of the total arsenic in the leachate was inorganic pentavalent arsenic [As(V)] and 10–30% was inorganic trivalent arsenic [As(III)].

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Properties of Southern Pine Wood Impregnated with Styrene

Holzforschung ◽

10.1515/hf.2003.049 ◽

2003 ◽

Vol 57 (3) ◽

pp. 333-336 ◽

Cited By ~ 14

Author(s):

W. Y. Chao ◽

A. W. C. Lee

Keyword(s):

Southern Pine ◽

Pine Wood

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