natural polymers Flashcards
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
