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Flashcards in natural polymers Deck (11):
1

cellulose

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

2

starch

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

3

chitin

deacetylation using sodium hydroxide
antibacterial and anti-inflammatory

4

natural polymers

cellulose
chitin
starch
perotein
chitin
chitosan
alginic acid
hyaluronic acid
xanthan gum
curdlan

5

bioplastics

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

6

problem of disposable plastics

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

7

advantage of biopolymers

renewable livestock
domestically grown
CO2 neutral
biodegradbale
biocompatible
energy saving

8

disadvantages

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

9

advantages of wheat gluten

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

10

drawbacks

poor water resistance
poor mechanical properties

11

natural polymers nanocrystal

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