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Flashcards in natural polymers Deck (11)
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1
Q

cellulose

A

repeat 1,4B
difficult to process
traditional viscose method use of CS2
new cellulose solvents = ionic liquid, NaOH/urea

2
Q

starch

A

repeating graph 1,4 and 1,6
liner amylase and branched amylopectin
gelatinization
poor wet mechanical properties

3
Q

chitin

A

deacetylation using sodium hydroxide

antibacterial and anti-inflammatory

4
Q

natural polymers

A
cellulose
chitin
starch
perotein
chitin
chitosan
alginic acid
hyaluronic acid
xanthan gum 
curdlan
5
Q

bioplastics

A
biopolymers shaped bua plasticization or cross linking 
PLA in corn
PHA form bacteria
port based =casein
starch based = cereplast 
vegetable oil = soyoyl
6
Q

problem of disposable plastics

A

limited recycling options
limited landfill space
incineration may release toxin
synthetic plastic exacerbate dependance on fossil fuel

7
Q

advantage of biopolymers

A
renewable livestock
domestically grown
CO2 neutral 
biodegradbale 
biocompatible 
energy saving
8
Q

disadvantages

A

more expensive
low end mechanical properties
lower service temperature
not as durable

9
Q

advantages of wheat gluten

A
film forming
low price 
biodegradable 
non toxic
adhesive
gas barrier and selectivity 
very high selectivity
10
Q

drawbacks

A

poor water resistance

poor mechanical properties

11
Q

natural polymers nanocrystal

A
reinforcing mechanical propertjes 
improve barrier properties 
stabilizing food emulsion 
swelling properties 
thermal stability