Introduction to Cellulose Flashcards
Which of the following elements cannot be found in cellulose?
a. Hydrogen
b. Carbon
c. Oxygen
d. Nitrogen
d. Nitrogen
The molar mass of cellulose in g/mol is:
162.14
The density of cellulose in g/cm3 is:
1.5
What is the melting point of cellulose in degrees Celsius?
260-270 degrees Celsius
What is the color of cellulose?
White
cellulose molecular formula:
C6H10O5
_______ is the most abundant organic compound on earth
Cellulose
It is chiral, tasteless and has no odor
cellulose
Cellulose first discovery of cellulose was in the year ____ –[French chemist by name AnselmePayen]
1838
It is an organic compound and is water-soluble and biodegradable.
cellulose
During the year 1980 it was used as to produce the first thermoplastic called ______.
celluloid
Monomer comes from mono-(____) and-mer(_____)
one; part
small molecules which may be joined together in a repeating fashion to form more complex molecules called polymers
monomer
comes from poly-(____) and-mer(part)
many
may be a natural or synthetic macromolecule comprised of repeating units of a smaller molecule (monomers)
polymer
- the most abundant organic (containing carbon) molecule on the planet due to its presence in plant cell walls and its slow rate of break down in nature
- structurally strong
Cellulose
Polysaccharide of glucose units in unbranched chains with ____________
ß-1,4,-glycosidic bonds
cellulose cannot form hydrogen bonds with water; thus, it is __________
insoluble in water
cellulose cannot be digested by humans because humans cannot breakdown __________
ß-1,4,-glycosidic bonds
3 Kinds of Sugar:
- Monosaccharide
- Disaccharide
- Polysaccharides
- contain just one molecule (ex. Dextrose, Glucose, Fructose and Galactose)
Monosaccharide
- complex structure of sugars (ex.Sucrose and maltose)
Disaccharide
- major classes of biomolecules; long chains of carbohydrate molecules, composed of several smaller monosaccharides (ex.starches and cellulose)
Polysaccharides
both the glucose, alpha glucose and beta glucose have the same structure, just the orientation of the hydroxyl group is ____________.
different
What is the difference between alpha glucose and beta glucose?
Alpha glucose: hydroxyl groups on the same side
Beta glucose: hydroxyl groups on opposite sides
synthesized at the ____________ and organized into micro-fibrils
plasma membrane (PM)
plant cell walls is made up of cellulose molecules arranged to form _________
microfibrils
number of combined microfibrils is needed to form a ______________
cellulose fiber
cellulose microfibril are __________ wide
5 to 12 mm
microfibrils contain ______ individual chains
20 to 40
made up of long unbranched chain of atleast ___ b-D-glucose molecules
500
this are linked with each other by ___________ linkage
B-1-4 glycosidic
with inverted glucose ______—
residue
- process of cellulose degradation
Cellulolysis
What are the methods of cellulose degradation?
a. Hydrolysis
b. Decomposition (microbial)
c. Heat
What are the intermediate units made from cellulose?
Cellobiose
Cellotriose
Cellotetraose
What is cellobiose?
Two glucose molecules connected
What is cellotriose?
Three glucose units connected
What is cellotetraose?
Four glucose units connected
What do endocellulases do?
Break down crystallinity in cellulose
What do exocellulases do?
Hydrolyze chain ends into smaller sugars
What do β-glucosidases do?
Hydrolyze disaccharides to form glucose
_____ (C6 Sugar); ______– (C5 Sugar)
Cellulose; Hemicellulose
- in this process, enzymes are used to hydrolyze the cellulose and hemicellulose
enzymatic hydrolysis
- produces cellulase enzymes
trichoderma reesei
–bacterium that converts sugars to pyruvate, which is then fermented to ethanol and carbon dioxide
Zymomonas mobilis(Z. mobilis)
bakers yeast used in brewery industry to produce ethanol from C6 sugars
Saccharomyces cerevisiae
uses mixed-acid fermentation in anaerobic conditions, producing organic acid (lactate, succinate, acetate, and formate) and ethanol acetate and carbon dioxide
(E. coli)
means the breakdown of cellulose when it is exposed to high temperature or heat
thermolysis
Thermolysisof cellulose occurs at ______ degrees, when decomposes into vapors of carbon dioxide and other ____.
350; aerosols
-process of decomposition of various compounds or materials with thermal decomposition at temperatures around 400–800°C in an oxygen-free atmosphere or contain very small amount of oxygen
Pyrolytic/Pyrolysis
Cellulose -Derivatives:
a. Cellulose Acetate
b. Acetate Compound Propionate (CAP)
c. Acetate Compound Butyrate (CAB)
d. Carboxymethylcellulose (CMC)
e. Carboxymethylcellulose (CMC)
f. Ethyl Cellulose (EC)
-synthetic compound derived from the acetylation of the plant substance cellulose
Acetate Compound (CA)
-commonly prepared by treating cellulose with acetic acid and then with acetic anhydride in the presence of a catalyst such as sulfuric acid.
Acetate Compound (CA)
-a cellulose ester wherein some of three hydroxyl groups of a cellulose unit (glucose combined with β1-4 glycoside bond) are substituted with acetyl and propionyl
Acetate Compound Propionate (CAP)
-can be synthesized by using an acid anhydride or an acid chloride as an acylatingagent
Acetate Compound Propionate (CAP)
-Excellent solubility, structural stability, light and weather resistance, good leveling, high gloss retention, good transparency.
Acetate Compound Propionate (CAP)
-They are widely used in the paint industry for top grade cars and furniture, as well as printing ink.
Acetate Compound Propionate (CAP)
-a mixed ester thermoplastic derivative of cellulose acetate that contains both acetate and butyrate functional groups.
Acetate Compound Butyrate (CAB)
-It has improved weathering resistance and lower moisture absorption compared to cellulose acetate
Acetate Compound Butyrate (CAB)
-it was designed for use where low-application viscosities at relatively high solids levels is needed. It is soluble in a wide range of solvents and compatible with many other resins
Acetate Compound Butyrate (CAB)
-the structure of cellulose ester, hydroxyl groups are co-esterified with acetic acid and butyric acid
Acetate Compound Butyrate (CAB)
-also known as cellulose gum
Carboxymethylcellulose (CMC)
-soluble in water at any temperature because of its highly hygroscopic nature, CMC hydrates rapidly
Carboxymethylcellulose (CMC)
-is a cellulose derivative with carboxymethyl groups (-CH2-COOH) bound to some of the hydroxyl groups of the glucopyranose monomers
Carboxymethylcellulose (CMC)
-used as a viscosity modifier or thickener, and to stabilize emulsions in various products, both food and non-food.
Carboxymethylcellulose (CMC)
-a derivative of cellulose in which some of the hydroxyl groups on the repeating glucose units are converted into ethyl ether groups
Ethyl Cellulose (EC)
-mainly used as a thin-film coating material for coating paper, vitamin and medical pills, and for thickeners in cosmetics and in industrial processes
Ethyl Cellulose (EC)
