FORMULA/CHEMICAL COMPOSITION Wood is not composed of a bunch of identical molecules, so it has no chemical formula. It turns out that wood contains lignite, an organic polymer which is a name applied to a group of complex organic chemicals. Wood also contains cellulose, which is a polysaccharides with (C6H10O5)n as its formula. The adhesive used for the layers is urea formaldehyde which is described as: C2H6N2O2 MATERIAL DESCRIPTION Plywood is a sheet material manufactured from thin layers or “plies” of wood veneer that are glued together with adjacent layers having their wood grain rotated up to 90 degrees to one another. EXTRACTION PROCESS The wooden veneers are cut to thicknesses 0.6 – 9.5 mm. The sheets are usually dried to a moisture content of less than 10 percent. This level is compatible with gluing and consistent with the moisture content to which plywood products will be exposed during construction. A number of adhesives can be used in the manufacture of plywood like urea-formaldehyde glue. This is a synthetic thermosetting glue and typical ingredients are water, defoamers, extenders (wheat flour) and urea-formaldehyde resin. After gluing, the layers of veneer are subject to pressure to ensure proper alignment and an intimate contact between the wood layers and the glue. The glue is allowed to partially cure under pressure. Pressing may be accomplished at room temperature (cold pressing), or at high temperature (hot pressing). Hot pressing equipment is used to cure some protein, some urea-formaldehyde, and all of the phenol-formaldehyde glues. BASIC PROPERTIES COMPREHENSIVE STRENGHT (N/M2) 31.000.000-41.000.000 TENSILE STRENGHT (N/M2) 31000000 STIFFNESS (N/M2) 40.000.000 DENSITY (KG/M3) 500-600 CARBON FOOTPRINT (AVERAGE KGCO2E/KG) 4.2 RECYCLABLE yes LASER yes SMALL LASER yes MILING yes 3D PRINTING yes ADVANTAGE IN THE CONTEXT OF DIGITAL FABRICATION Plywood is a very versatile material. It is used for constructions, interior design or even fashion. Due to its composition of rotated wood layers it is very durable. It can be worked on with different machines including CNC milling machines and laser cutter. If powdered it may be even used for 3D printing. To recycle it, the shredded parts are reused again for composite materials. MATERIAL SUPPLIERS:
address |
km from IAAC |
€/m2 |
€/2.5×1.22 [m] |
€/kg |
link |
||
1 | Xilos | Passatge de la Vinyassa08005 Barcelona |
0.3 |
5.08 |
15.49 |
2.93 | – |
2 | Gilabert | Rambla Guipúscoa, 177 – 191 |
1.8 |
5.19 |
15.57 |
2.99 |
http://www.fustesgilabertsa.com/ |
3 | Gabarro | Crtr. antiga de València s/n 08850 Gava (Barcelona) |
25.3 |
5.21 |
16.0 |
3.00 |
http://www.gabarro.com/en/ |
4 | Fustot | Lorenzale, 24, bajos 08026 Barcelona |
3.5 |
6.43 |
19.61 |
3.70 | www.fustot.cat/es/ |
REFERENCES Dragon Skin Pavillion 2011
http://www.evolo.us/architecture/dragon-skin-pavilion-is-a-digitally-fabricated-plywood-sculpture/
Biominicry fashion 2011
http://www.fashitects.com/2011_10_01_archive.html