文档介绍：PolymerPolymerPolymer PhysicsPhysicsPhysics
高分子物理高分子物理高分子物理
33 PolymerPolymer SolutionsSolutions
高分子溶液
Importance to study polymer solutions
研究高分子溶液的意义
Dilute solution Semi-dilute solution Concentrated solution
Theoretical study ~2% Application
Chain conformation Study on dilute Adhesives
Molecular weight solution is of key Coating
Radius of gyration Plasticized plastics
importance on the Polymer blends
formation of
polymer science
The solubility parameter
溶度参数
Dissolution of polymers
高分子的溶解
Dissolution process is much slower than low
molecules
Crosslinked polymers can only swell (溶胀),not
dissolve (溶解)
The higher the molecular weight of the polymer,
the more difficult it is to select a good solvent
Polymer-polymer mutual solutions are even
more difficult to attain
Free energy of dissolution
溶解自由能
∆GM = ∆H M −T∆S M
? >0
∆HM < 0 (with special interaction):
dissolvable
∆HM > 0 (without special interaction):
undissolvable
Definitions of Solubility parameter
溶度参数的定义
For non-polar system:
2
⎡ 1 1 ⎤
⎛∆E ⎞ 2 ⎛∆E ⎞ 2
∆H = V ⎢⎜ 1 ⎟−⎜ 2 ⎟⎥ v v
M M ⎢⎜ V ⎟⎜ V ⎟⎥ 1 2
⎣⎝ 1 ⎠⎝ 2 ⎠⎦
Total volume Square root of CED Volume fraction
The solubility parameter is defined as the
square root of coherent energy density
1
δ= (∆E /V ) 2
Solubility parameter and solubility
溶度参数与溶解度
Hildebrand equation (for non-polar system)
2
∆H M = VM [δ1 −δ 2 ] v1v2
[δ1 −δ 2 ] Solubility
Solubility parameter of polymers
Polymer δ(cal/cm3)1/2 δ(J/cm3)1/2
Polybutadiene 聚丁二烯
Polyethylene 聚乙烯
Poly(methyl methacrylate)
聚***丙烯酸甲酯
Polytetrafluorethylene 聚四***乙烯
Polyisobutene 聚异丁烯
Polystyrene 聚苯乙烯
Cellulose triacetate 三醋酸纤维素
Nylon 66 尼龙66
Poly(ethylene oxide) 聚氧乙烯
Poly(vinyl chloride) 聚***乙烯
Solubility parameter of solvents
Solvent δ(J/cm3)1/2 H-bonding Group
Acetone *** m
Benzene 苯 p
n-But