Nanoparticles

Question 1

what are the three categories particles are placed in

Answer 1

coarse particles
fine particles
nanoparticles

Question 2

tell me 5/6 properties of nanoparticles

Answer 2

• huge surface area to volume become good catalyst, take place on surface of catalyst so bigger surface so more collisions so faster
• new cosmetics as small particles for better protection for white marks on skin
  sunscreen. block UV light from sun
• nano-medicine, tiny fullerenes absorbed easily by the body, most deliver drugs right into cells
• lubricant coating using fullerenes used in gears
• conduct electricity used in electric circuits
• added to plastics in sports equipment much stronger and more durable without adding much mass
• silver nanoparticles added to polymer fibres to make surgical masks and wound dressings, gives fibres antibacterial properties

Question 3

what are the risks of nanoparticles

Answer 3

• products must be tested properly, and some have available before harmful effects on human health have been investigated
• nano particles don’t break down easily so start to build up and cause lung inflammation

Question 4

what is polymerisation

Answer 4

where different monomers are used to make a range of polymers

Question 5

what are stronger polymers used for

Answer 5

high density poly(ethene) used to make water pipes

Question 6

what are light and stretchy polymers used as

Answer 6

• low density for plastic bags and bottles

Question 7

what is poly(styrene) foam used for

Answer 7

packaging to protect fragile things and a thermal insulator

Question 8

what are heat resistant polymers used as

Answer 8

• melamine for plastic kettles

Question 9

what are the material type of ceramics

Answer 9

brittle

Question 10

what is clay ceramics and how are they formed

Answer 10

• from weathered rock and decomposed rock

soft when dug up but easy to mould into shapes

hardened by high temperatures

ideal for building material as withstand weight of bricks on top

Question 11

what is glass ceramic and what is it used for

Answer 11

glass is majority soda lime glass made from heating limestone, sand and sodium carbonate until melted when cooled forming glass

glass transparent and strong but moulded when hot and brittle when thin

Question 12

what are composites

Answer 12

made of two components matrix and reinforcement
- carbon fibre made composites made by carbon atoms bonded to make carbon nanotubes which are held w polymer resin matrix

expensive but light and strong

Question 13

what are metals

Answer 13

Shiny, malleable

mixed with other elements to form alloys, which have different properties to the elements they contain

Good conductors of heat and electricity

Question 14

WHAT ARE THE FEATURES OF POLYMERS
M
P
D
C/I
L

Answer 14

flexible 
easily moulded
cheaper
less dense good for designing w low mass
insulators
can degrade

Question 15

what are the features of ceramics

Answer 15

• insulators
• brittle
• strong
• dont degrade or corrode hence glass not plastic windows

Question 16

metal features

Answer 16

• conductors
• less brittle stiff
• strong
• dont corrode or degrade if corrosion resistance

Question 17

composites features

Answer 17

• depends on matrix and reinforcement combination and polymers specific purpose
• expensive