8
3.
DERIVATIVES OF WOOD
Derivatives of wood are not taken directly from cutting logs but from sheets, fibres
or chips of wood which are compressed and glued. Derivatives include
engineered
wood
and
cellulose materials
.
3.1.
Engineered wood
Type
Source
Characteristics
Plywood
Formed by gluing thin
sheets with synthetic
resins. The fibres on
each sheet are at a 90°
angle to each other. Very
resistant.
Can
warp
5
due to
changes in humidity.
Chipboard
Made with wood
shavings
6
and chips
glued by compression.
Fragile but not easily
deformed. Rough
surface. Seriously
affected by humidity.
Fibreboard
Fibres come from
grinding
7
chips. This
produces tiny wood
threads which are glued
using synthetic resins to
make planks.
Polished surface, fine
texture. Very resistant
to humidity.
Understand
14.
Find out about the process of recycling paper. Which parts of the
process of making paper from wood are not included in recycling?
logging
strip the bark
grind
the wood
wash and bleach
8
cellulose paste
liquid paste
press with
rollers
smooth
with rollers
remove
water
dry with hot rollers
roll up
and cut
The process of making paper from wood
Understand
10.
What are the advantages
anddisadvantagesofusing
natural wood instead of
engineered wood?
11.
What kind of wood
would you use to make
the following?
a)
a wooden handle
b)
a boat
c)
a guitar
d)
a window frame
e)
a decorative object
f)
parquet floor
12.
Find out possible uses
of plywood, chipboard
and fibreboard.
Apply
13.
What kind of engineered
wood would you use for
your puzzle? Explainwhy.
Analyse
9.
Look up information
about the world’s largest
forests. How we can
help save them?
Amazon forest, Peru
3.2.
Cellulose materials
These are made from the cellulose of wood. They include paper, cardboard, silk
paper and card.
Wood is pulped and mixed with water and chemicals to make a cellulose paste.
This paste is compressed and made into layers with a machine so that it turns into
sheets.
❚❚
Engineered wood is made
from shavings, chips and
sheets.
❚❚
Paper is mostly made of
cellulose.
Key concepts
5
warp
:
bend out of shape
6
shavings
: very thin strip cut from surface
7
grind
: make into a powder by crushing
8
bleach
: make white with chemicals
ADVANCE
EDITION
