Download Cellulose structure： The history of cellulose： Cellulose was

Cellulose structure：
The history of cellulose：
Cellulose was discovered in 1838 by the French chemist Anselme Payen, who isolated it from plant
matter and determined its chemical formula. Cellulose was used to produce the first successful
thermoplastic polymer, celluloid, by Hyatt Manufacturing Company in 1870. Production of rayon
("artificial silk") from cellulose began in the 1890s and cellophane was invented in 1912. Hermann
Staudinger determined the polymer structure of cellulose in 1920. The compound was first
chemically synthesized (without the use of any biologically derived enzymes) in 1992, by
Kobayashi and Shoda
How it is synthesized commercially or biologically：
Cellulose is a source of
energy for several types of
microbes. Large amounts of
cellulose is degraded to
glucose by both bacterial and
fungal microbes. The glucose
derived from cellulose
degradation is then used by
other microbes as a carbon
source to produce energy.
Many fungi, specifically the
members of Basidiomycetes
perform critical ecological
function by degrading
cellulose present in decaying
wood.
Some animals can digest
cellulose. When an herbivore,
say a cow, consumes a plant,
like grass, bacteria in their
intestinal tract are able to break down the cellulose into smaller parts that the cow's own digestive
system can absorb.
Some bacteria can actually produce their own cellulose, making a kind of film. The acetic acid
bacteria used in the production of wine and beers is one of these types. The synthesized cellulose
forms a film around the bacterial cell and becomes a kind of matrix, called a pellicle, which helps
the acetic acid bacteria to float on the surface and access oxygen needed for their survival.
Cellulose’s properties：
Cellulose, with the formula (C6H10O5) is an
organic compound which consists of a linear
chain made up from 'several
hundred to over ten thousand
β(1→4) linked D-glucose
units'’or in simpler terms, it
is made of repeated units
of the monomer glucose. It
is the ability of these
chains to hydrogen-bond
together into fibres
(microfibrils) that gives
cellulose its unique properties
of mechanical strength and
chemical stability.created by both
plants and animals. About 33% of all plant
mater is cellulose (the cellulose content of
cotton is 90% and that of wood is 40-50%)，although usually considered a plant material, it can
also be produced by some bacteria.
Cellulose uses in society：
Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a
wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from
energy crops into biofuels such as cellulosic ethanol is under investigation as an alternative fuel
source. Cellulose for industrial use is mainly obtained from wood pulp and cotton.
Some animals, particularly ruminants and termites, can digest cellulose with the help of symbiotic
micro-organisms that live in their guts, such as Trichonympha. In humans, cellulose acts as a
hydrophilic bulking agent for feces and is often referred to as a "dietary fiber".
Some problems associated with cellulose：
Cellulose is a popular insulation material that is also environmentally friendly. However, it can
cause some problems, including respiratory issues
① Loose Cellulose is Heavier than Fiberglass.The weight of the insulation material may cause
problems, especially when it is meant for locations like ceilings. Loose cellulose weighs more
than the same amount of rockwool or fiberglass. It is said that the amount of cellulose required
to cover a given area weighs three times more than loose fiberglass required for that area. This
could be a problem, if you choose cellulose insulation for weak ceilings.
② Wet Spray Cellulose Requires Proper Drying Time.If you opt for wet spray cellulose, you must
have sufficient time to wait till it dries properly. Some people use large space heaters for drying
the insulation. The insulation has to be dry, before you apply a drywall or sheet-rock. A moisture
meter can be used to check the moisture levels, before installation. Though it requires some
time to dry, wet spray cellulose provides a better seal and may not settle.
③ Dry-blown Cellulose may Sag and Settle.It has been noticed that dry-blown cellulose insulation
settles over time and gets compact, thereby creating air spaces and reducing the R-value. It is
also prone to moisture problems, which can lead to mold and mildew. This in turn affects the
durability of the insulation. However, the problem of settling can be overcome with dense
packing, which has to be done by an experienced person.
④ Blown-in Cellulose Insulation Releases Dust.Being made of minutely shredded newspaper,
cellulose insulation may release dust through small holes. Mostly, this happens in case of
inadequate or improper sealing. Dust that stays indoors for longer duration may cause health
problems in the inhabitants. It may also carry particles of chemicals like borax. Exposure to
dust is a common problem that is encountered during installation of cellulose insulation.
Certified breathing masks have to be used in such cases. Another option is to use low-dust
cellulose, which contains dampeners.
⑤ Cellulose Insulation Health Hazards.While exposure to dust is a cause of concern, the
chemicals in cellulose insulation may also cause some health problems. Chemicals in inks and
dyes of newspaper and those in additives like fire retardants and adhesives, may cause allergic
reactions in sensitive people. If exposed to the dust laced with chemical particles, symptoms
like irritation of the eyes, nose, and throat may develop. Some people may experience cough
and skin dryness. Long-term exposure to a high concentration of these chemicals may cause
severe symptoms.