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1. Function of sensing: this kind of smart material could sense the environment and
condition, such as load, stress, strain, light, heat, electricity and so on;
2. Function of feedback: materials with feedback function could compare the output information and input information and provide information for controlling
system;
3. Function of information recognition and accumulation: materials could identify
all kinds of information, which can be obtained from the sensor network and
accumulate them.
4. Response ability: smart materials with response ability could respond to the
change of external environment and internal conditions timely and also take necessary actions dynamically.
5. Self-diagnosis ability: smart materials with self-diagnosis ability could selfdiagnose and adjust the problems such as system failures and misjudgments by
analyzing and comparing the present situation of the system with the past.
6. Self-repairing ability: smart polymers could repair local damage or destruction
by means of the regeneration mechanism such as self-reproducing, self-growing,
in situ healing and so on.
7. Self-adaptive ability: smart materials with self-adaptive ability could automatically adjust its structure and function in time according to the changing external
environment and conditions. Then, the state and behavior are changed correspondingly in an optimized way for material system to meet external changes.
As a unique kind of smart polymer material, shape memory materials could perceive change of environment (e.g. temperature, force, chemical solvent, electricity,
magnetism, among others.) and respond to these changes. After completing the
above procedures, the shape memory materials recover to pre-setting shape through
adjusting the mechanical parameters. As a kind of smart materials, shape memory
performance endows the materials with propestive potential applications. Therefore,
the shape memory materials have been developed since 1963. W. J. Bueler firstly
discovered the memory effect of Ni-Ti alloy by accident, implying shape memory
alloy materials with engineering significance does emerge. Hereafter, the scientists
developed various kinds of shape memory materials, which can be classified as
follows:
1. Shape memory alloy: Ni-Ti alloy, Cu-Ni-Mn, Fe-Mn-Si;
2. Inorganic non-metal shape memory materials: garnet, mica glass;
3. Shape memory composite materials: aluminum embedded with shape memory
nickel-titanium alloy wire.
4. Shape memory polymers (SMPs): shape memory poly(urethane) (PU), shape
memory crosslinked poly(ethylene) (PE) and shape memory hydrogels;
SMPs have the following advantages compared to shape memory alloys and
shape memory ceramics: strong memory effect, low sensing temperature, cheap,
easy processing and a wide range of applications. Thus, SMPs have attracted a lot
of attention from researchers. A. Charlesby firstly described memory effect of radiation-crosslinked PE. Then National Aeronautics and Space Administration
Z. Gao and G. Gao
1. Function of sensing: this kind of smart material could sense the environment and
condition, such as load, stress, strain, light, heat, electricity and so on;
2. Function of feedback: materials with feedback function could compare the output information and input information and provide information for controlling
system;
3. Function of information recognition and accumulation: materials could identify
all kinds of information, which can be obtained from the sensor network and
accumulate them.
4. Response ability: smart materials with response ability could respond to the
change of external environment and internal conditions timely and also take necessary actions dynamically.
5. Self-diagnosis ability: smart materials with self-diagnosis ability could selfdiagnose and adjust the problems such as system failures and misjudgments by
analyzing and comparing the present situation of the system with the past.
6. Self-repairing ability: smart polymers could repair local damage or destruction
by means of the regeneration mechanism such as self-reproducing, self-growing,
in situ healing and so on.
7. Self-adaptive ability: smart materials with self-adaptive ability could automatically adjust its structure and function in time according to the changing external
environment and conditions. Then, the state and behavior are changed correspondingly in an optimized way for material system to meet external changes.
As a unique kind of smart polymer material, shape memory materials could perceive change of environment (e.g. temperature, force, chemical solvent, electricity,
magnetism, among others.) and respond to these changes. After completing the
above procedures, the shape memory materials recover to pre-setting shape through
adjusting the mechanical parameters. As a kind of smart materials, shape memory
performance endows the materials with propestive potential applications. Therefore,
the shape memory materials have been developed since 1963. W. J. Bueler firstly
discovered the memory effect of Ni-Ti alloy by accident, implying shape memory
alloy materials with engineering significance does emerge. Hereafter, the scientists
developed various kinds of shape memory materials, which can be classified as
follows:
1. Shape memory alloy: Ni-Ti alloy, Cu-Ni-Mn, Fe-Mn-Si;
2. Inorganic non-metal shape memory materials: garnet, mica glass;
3. Shape memory composite materials: aluminum embedded with shape memory
nickel-titanium alloy wire.
4. Shape memory polymers (SMPs): shape memory poly(urethane) (PU), shape
memory crosslinked poly(ethylene) (PE) and shape memory hydrogels;
SMPs have the following advantages compared to shape memory alloys and
shape memory ceramics: strong memory effect, low sensing temperature, cheap,
easy processing and a wide range of applications. Thus, SMPs have attracted a lot
of attention from researchers. A. Charlesby firstly described memory effect of radiation-crosslinked PE. Then National Aeronautics and Space Administration
Z. Gao and G. Gao