Materi SMP kelas 3

1. MATERI
AL
PROPER
TIESBy: Fadhilah Utami A

2. 1. Fiber Materials
a similar network of yarn or long
ribbons derived from animals or
plants. Fiber is used for making
paper, textile, and rope (the main
ingredient of the rope). consisting
of natural fibers and synthetic
fibers
Fiber properties: not rigid and
flammable.

3. Natural Fibers
 Natural fiber materials obtained from plants,
animals, and minerals.
 Plant fibers are obtained from plant cellulose,
for example from cotton, kapok, and hemp.
Examples of textiles from cellulose are cotton
and linen.
 Animal fiber in the form of protein fibers can be
obtained from sheep's hair, mesh yarn produced
by
profit spider, and silkworm cocoons.
Examples of textiles of protein fibers
are wool and silk.
 Mineral fiber, commonly made

4. Synthetic
Fibers
• Synthetic fibers are
fibers made by
humans, their basic
ingredients are not
available directly from
nature.
• Examples of fabrics
made of synthetic
fibers are rayon,

5. Mixed Fiber
 Use of natural and synthetic
ingredients can be mixed to
improve the quality of the
ingredients. Examples of
textiles of mixed fiber
materials are: TC (Tetoron Cotton) mixture
of polyester and cotton.
 TR (Tetoron Rayon) mixture
of polyester and rayon.

6. 2. Rubber Materials
 Rubber is produced by a
rubber tree in the form of
latex-like milk called latex.
 Latex is obtained by
tapping, by slashing the
bark of the tree or on the
part of the plant cortex.
 Chemically natural rubber
is a hydrocarbon
compound which is a
natural polymer of natural
latex clumping and is a
polyisoprene
macromolecule (C5H8) n.

7. Properties of Natural
Rubber
Natural rubber has good
elastic or resilient power,
good plasticity,
easy to process, not easy to
wear (not easy to run out of
friction), and not easy to heat,
have high resistance to crack,
hold repetitive beat, and also
high stickiness to various
materials.

8.  Synthetic
rubber has
several
properties,
namely:
Resistant to
high
temperature or
heat, oil, air
effect, and
 Synthetic rubber is made from
raw materials derived from
petroleum, coal, oil, natural
gas, and acetylene.

9. Here are some types of synthetic
rubber with its properties and
usefulness.
 NBR (Nytrile Butadiene Rubber).
NBR has a high resistance to oil,
used in the manufacture of rubber
pipes for gasoline and oil,
membranes, seals, gaskot, and
other equipment widely used in
motor vehicles.
 CR (Chloroprene Rubber), CR with
flame resistant characteristics, is
used as rubber pipe material, cable
wrapper, seal, gaskot, and carrier
belt.
 IIR (Isobutene Isoprene Rubber),

10. 3. Clay
Material
Clay is the basic material used in making
ceramics. Clay chemically includes alumina
hydrosilicate. The physical properties of the
clay are plastic when it is wet, hard if dry, and
when burned becomes solid and strong.
Generally, goods made from clay are called
ceramics. However, not all ceramics today
come from clay.

11. Ceramics divided into two groups:
1) Traditional Ceramics
Traditional ceramic raw material from clay.
Based on the composition of the clay and its combustion
temperature, traditional ceramics are divided into pottery
(terracotta), earthenware, stoneware, and porcelain.
2) Fine ceramics
Fine ceramics or engineering ceramics whose raw materials
are from metal or metal oxides, such as: metal oxides
(Al2O3, ZrO2, MgO,)
These fine ceramics are used as heating elements,
semiconductors, turbine components, and in the
medical field.

12. 4. Glass Material
 A glass is a solid, which is a
chemical compound with a
complex arrangement,
obtained by freezing the
melt through cooling.
 Ready-made glassware
includes home furnishings
(glass plates, glass cups,
glass bottles, etc.),
laboratory equipment (test
tubes, glass pipes, glass
beads, magnifying glass,
etc.), building or industrial
materials such as window

13. The Properties of Glass
Materials
 It is resistant to water, gas, odors and microorganisms.
 Can not react with packaged goods (chemicals).
 Can be recycled.
 Can be closed again after opening.
 Translucent so that its contents can be seen.
 Provide added value for the product (aesthetic value).
 Rigid and strong so that it can be stacked without
damage.
 Glasses can be stored for a long period without damage.

14. 5. Wood
Materials
Wood is used for various
purposes because it
contains important
components of cellulose,
lignin, and extractive
compounds (certain
compounds that can be
taken from wood).
Utilization of wood
adapted to its properties.
Woods of different tree
species have different
properties.

15. Properties of Wood
1. Specific Weight
Specific gravity relates to the strength of the wood. In
general, the higher the density of wood, the wood is also
stronger.
2. Durability
The durability of wood is due to the content of extractive
compounds in the wood. Teak wood has extractive
tectoquinon, ulin wood contains silica. Both types of wood
have a high degree of durability.
3. Color
Colorful woods are caused by color fillers in wood, their
position in stems, tree age and environment. The wood
from the old tree is darker than the young wood even

16. 4. Texture
Texture is a relative measure of wood fiber,
which is coarse, medium, and smooth
texture.
5. Impression Profit
Impression of touch is the impression gained
when touching the surface of the wood
(rough, smooth, slippery, cold, oily, and
others). The impact of each type of wood
varies depending on the texture of wood,
Properties of Wood

17. 6. Smell and Pain
The smell and taste of wood easily disappear when
old wood is stored in the open air. Some wood
species have a stimulating odor. To express the
smell of the wood, often used the smell of something
commonly known things such as the smell of onion
(kulim wood) and the smell of tanners (teak).
7. Decorative Value
Decorative value relates to beauty. Wood decorative
values depend on the pattern of color distribution,
fiber direction, texture, and appearance of certain
patterns.
8. Hardness or Density
Wood hardness is directly related to wood weight.
Properties of Wood