lecture il2

1
(No Transcript)
2
BIOMATERIALS are defined as Any
pharmacologically inert material that is used to
direct, supplement or replace the functions of
living tissue.
3
BIOMATERIALS are defined as Any
pharmacologically inert material that is used to
direct, supplement or replace the functions of
living tissue.
4
?
Bone cement containing antibiotics
IUDs
DDSs
BDG Polymers
Biofunctional materials
5
BIOMATERIAL A material that is used in the
treatment of patients, that comes in contact
with living tissue for a significant period of
time, so that the interactions developed between
the material and the tissue are a key part of
the treatment.
6
BIOMATERIAL Natural or synthetic materials that
come in contact with physiologic fluids or living
tissues, excluding the epidermis, for
prosthetic, therapeutic, directing or storage
purposes, where any pharmacologic activity
related to it, is secondary and not its main
objective.
7
TYPES OF BIOMATERIALS
METALS
CERAMICS
CARBONS
NATURAL TISSUES
COMPOSITE MATERIALS
POLYMERS
8
COMPOSITE MATERIALS
Different materials
Different materials of the same family
Classic Composite Materials
9
TYPES OF BIOMATERIALS
METALS
CERAMICS
CARBONS
NATURAL TISSUES
COMPOSITE MATERIALS
POLYMERS
10
???????
1 ??????????????? 2 ?????? ?????
????? 3 ??????????? 4 ??? ??????? 5
?????? ?????
???????
1 ??????? ???? 2 ???????????? 3
?????????? . . . 4 ??????
11
POLYMERS
ELASTOMERS
PLASTICS
FIBERS
12
Percutaneous devices - Implanted devices
- Extra-corporeal devices - Load-bearing implants
- Implants as part of organs - Implants for soft
tissue - Various -
Catheters
Pacemakers
Blood oxygenators
Hip prostheses
Heart valves
Artificial blood vessels
Sutures, contact lenses, IOLs, DDSs,
13
Biomaterials and the devices made from them,
occupy an increasingly important role in modern
clinical medicine.
14
Already back in 1988, in the United States
alone, an estimated 11 million persons had at
least one medical device implanted!!
2,5 million of these had lens implants, 1,3
million had artificial joints, 460,000 had
pacemakers, 253,000 had artificial heart
valves,
15
?
REQUIREMENTS!!
(1) Has the required initial properties (chemical
physical, biological, )
(2) Retains its properties in vivo or changes
them as programmed (one hour, month, year, )
(3) Easy cleaned, manufactured and sterilized
(4) Does not cause any negative reactions in the
host (blood coagulation, hemolysis,
inflammatory response, immunogenecity,
carcinogenicity, ... )
16
THE GOAL OF THE COURSE IS
NOT
17
The Biomaterials Yellow Pages !!!!!
NOT
18
THE GOAL FO THE COURSE IS
To present and discuss the phenomena presently
considered to play a key role in determining the
Biological Performance of the Biomaterial/Implant
.
19
Introduction History, definitions,
The polymers themselves
Biological Performance
The interface
Nanosized biomaterials
Tissue Engineering
20
(No Transcript)
21
(No Transcript)
22
Their molecular weight is high.

• Polymeric compounds exhibit a number of unique
  features

They consist of repeating units (mers).
Polymers are usually polydisperse.
23
OLIGOMERS (oligo few) MW lt 1500 DP lt 10
TELOMER (teleos end) A monomer unit at the end
of a polymer molecule
24
POLYMERS
LOW MW(av) 1,500 5,000 DP 20 100 Chain
length lt 500 A
MEDIUM MW(av) lt 10,000 DP lt 1,000 Chain length lt
2500 A
25
POLYMERS
HIGH MW(av) gt 10,000 DP gt 1,000 Chain length gt
2500 A
26
MOLECULAR WEIGHT
MT
27
Properties versus molecular weight
28
MOLECULAR WEIGHT
MW W/N
W Total sample weight N Number of moles in
the sample
29
DIFFERENT CHAIN LENGTHS ! ! !
AVERAGE MOLECULAR WEIGHT
MOLECULAR WEIGHT DISTRIBUTION
30
DEGREE OF POLYMERIZATION DP
The number of repeating units in the molecule
___ __ MW DP x MWmer
31
NUMBER-AVERAGE MW
- Number of molecules Xi MWi A given molecular
weight
32
WEIGHT-AVERAGE MW
- Weight fraction Wi MWi - A given molecular
weight
33
POLYDISPERSITY
Mw / Mn

• Breadth of distribution.
• 1 monodisperse, 2 good
• 5-10 common, 10 commercial

34
and what about the Molecular Weight
Distribution??
35
MW determination
Absolute methods
Relative methods
36
ABSOLUTE METHODS The quantity measured is
theoretically related to the average molecular
weight.
RELATIVE METHODS The quantity measured is in
someway related to the molecular weight, but the
exact relation must be established by calibration
with one (or more) of the absolute methods.
37

• LLEGUE HASTA AQUI!!

38
We end up with different kinds of molecular
weight averages, depending on the way in which we
obtained the data.
39
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
40
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
41
The two main polymerization mechanisms are
ADDITION
CONDENSATION
42
CH2 CHX
43
CH2 CHX
-Phenyl
-Cl
-H
-CONH2
-COOH
-CH3
-F
-COOMe
-OH
44
Tacticity of Polymers
PP

• Isotactic
• Syndiotactic
• Atactic

45
The two main polymerization mechanisms are
ADDITION
CONDENSATION
46
R-OH

R-CO-OH
R-CO-OR
47
HO-R-OH

HO-OC-R-CO-OH
HOOC-R-COO-R-OH
-R-O-OC-R-CO-O-R-O-COR-
48
HO-CH2-CH2-OH
HO-OC-CH2-CH2-CH2-CH2-CO-OH
49
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
50
ELEMENTS
F
Si
FUNCTIONAL GROUPS
Acrylics
Polyolefins
Polyesters
Polyamides
Polyurethanes
Polycarbonates
51
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
52
LINEAR
53
BRANCHED
54
CROSS-LINKED
55
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
56
LINEAR
THERMOPLAST
57
THERMOSET
CROSS-LINKED
58
BRANCHED
THERMOSET
59
THERMOPLAST
BRANCHED
60
BRANCHED
THERMOPLAST
61
?
The two main polymerization mechanisms are
ADDITION
THERMOSET
CONDENSATION
62
THERMOSET
ADDITION
AT LEAST, TWO DOUBLE BONDS!!
63
THERMOSET
CONDENSATION
64
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
65
Tg
Not OrdEReD
AMORPHOUS
CRYSTALLINE
ORDERED
Tm
66
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
67
POLYMERS
ELASTOMERS
PLASTICS
FIBERS
68
STRENGTH
STIFFNESS
ELONGATION AT BREAK
TOUGHNESS
69
Synthetic route
Chemical nature
End use
POLYMERS
Mechanical properties
Structure
Physical state
Thermal behavior
70
ADDITIVES
BLENDS
IPNs
COPOLYMERS
71
Interpenetrating
Polymeric
Network
We start from already crosslinked P1
We also have M2, I, Xler (?) and solvent (?)
72
COPOLYMERS
RANDOM
AABABBBAABBABBABABBABBA
ALTERNATE
ABABABABABABABABABABABAB
BLOCK
AAAAAABBBBBBBAAAAABBBBBB
GRAFT
73
WHATS THE FUNDAMENTAL DIFFERENCE BETWEEN
BLENDS, IPNs AND COPOLYMERS ????!!???
74
(No Transcript)
75
(No Transcript)
76
Falta MW y Tg y Tm
77
FALTA SUSITA!!
78
(No Transcript)
79
(No Transcript)
80
(No Transcript)