Mechano-sorptive creep of Portuguese pinewood chemically modified

• Autorzy: Lopes D. B. , Mai C.
• Języki publikacji: EN

Abstrakty

EN

The effect of chemical modification on mechano-sorptive creep in bending was studied by experimental work. Stakes with 20 × 20 × 400 mm RTL of Portuguese wood species (Pinus pinaster Aiton) modified with 1,3-dimethylol-4,5- dihydroxyethyleneurea (DMDHEU), m-methylated melamine resin (MMF), tetraethoxysilane (TEOS) and amid wax (WA) were measured under asymmetric moistening conditions over a period of 42 days (app. 1000 hours) with stress level (SL) of 12 MPa, according to ENV 1156. The cell wall treatments (DMDHEU and MMF resins) had shown significant reduction of creep (creep factors, kc) when compared to untreated wood under similar conditions. Both types of resins and levels of treatments (different WPG) did not shown significant effects. In the lumen fill treatments, deposit material of TEOS did not affected the creep behaviour (kc); Wax treatment was shown a particular compliance of creep due to avoid exchange moisture (by the hydrophobic effect of wax). The anti-creep efficiency (ACE) correlated better than other mechanical or physical properties imparted by the modification process.

Słowa kluczowe

EN

creep factor; Portuguese pine wood; pine wood; chemically modified wood; modified wood; mechano-sorptive effect; wax; resin

• Wydawca: -
• Czasopismo: Folia Forestalia Polonica. Series A . Forestry
• Rocznik: 2014
• Tom: 56
• Numer: 1
• Opis fizyczny: p.30-44,fig.,ref.

Twórcy

autor

Lopes D. B.

• School of Engineering - Polytechnic of Porto, Rua Dr.Antonio Bernardino de Almeida 431, 4200-072 Porto, Portugal

autor

Mai C.

• Wood Biology and Wood Products, Busgenweg 4 - 37077, Germany

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