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nanoadhesives
Adhesives are substances that join two surfaces together. The surfaces can be of dissimilar materials. Historically, many adhesives
were made from natural materials, including plant resins, gums,
and many other substances. Adhesives made of animal glues were
widely used in ancient Egypt, for example, in making veneers. Egg
whites became widely used in the Medieval art world. Ultimately,
glues were made from a wide variety of both organic and inorganic
substances (fish, rubber, caseins, and minerals). The introduction
of synthetic adhesives based on elastomers, thermosetting and
thermoplastic polymers, and other materials has led to many new
and improved types. Their use has become amazingly widespread.
Adhesives are used in everything from simple consumer products
to automobiles. They allow various materials to be adhered or
bonded together with comparative ease and speed, thus expediting
manufacturing processes for products. Their effects on joined materials are normally benign. Adhesive layers are relatively thin. Adhesives and many sealants are closely related in a technical sense and
are often lumped together in discussions and even by promulgating industries. New synthetic adhesives are really quite remarkable.
This does not mean, however, that the quest for ever-better adhesives is in any way lessened. The potential of using nanomaterials
to enhance existing adhesives or to produce new ones is a major
applied research domain, particularly since the potential market for
improved products is so huge. There have already been notable successes in this regard. Nanoadhesives that are bio-inspired—notably
the “gecko” nanoadhesives—have become meaningful symbols for
what nanotechnologies can accomplish.
Before looking at bio-inspired adhesives, we should look at
how nanomaterials can yield improvements to existing kinds of
adhesives. Many adhesives are targeted for particular surface types
and others for more general applications. Mechanisms for adhesion
are primarily either mechanical or chemical. Mechanical means
involve the adhesive substance providing a type of interlocking
mechanism, typically by the substance filling small pores in each
of the surfaces. Chemical means are more varied and include direct
chemical bonding and the development of intermolecular forces.
Corresponding to these several mechanisms are various types of
adhesives that have quite different application methods and use
properties. Reactive adhesives, including common two-part epoxies,
provide direct chemical bonding after being applied on thin layers
to a surface and can be quite strong. Light-sensitive adhesives are
cured by exposure to light of specific wavelengths (often ultravioNanoproduct Forms
nanoadhesives
Adhesives are substances that join two surfaces together. The surfaces can be of dissimilar materials. Historically, many adhesives
were made from natural materials, including plant resins, gums,
and many other substances. Adhesives made of animal glues were
widely used in ancient Egypt, for example, in making veneers. Egg
whites became widely used in the Medieval art world. Ultimately,
glues were made from a wide variety of both organic and inorganic
substances (fish, rubber, caseins, and minerals). The introduction
of synthetic adhesives based on elastomers, thermosetting and
thermoplastic polymers, and other materials has led to many new
and improved types. Their use has become amazingly widespread.
Adhesives are used in everything from simple consumer products
to automobiles. They allow various materials to be adhered or
bonded together with comparative ease and speed, thus expediting
manufacturing processes for products. Their effects on joined materials are normally benign. Adhesive layers are relatively thin. Adhesives and many sealants are closely related in a technical sense and
are often lumped together in discussions and even by promulgating industries. New synthetic adhesives are really quite remarkable.
This does not mean, however, that the quest for ever-better adhesives is in any way lessened. The potential of using nanomaterials
to enhance existing adhesives or to produce new ones is a major
applied research domain, particularly since the potential market for
improved products is so huge. There have already been notable successes in this regard. Nanoadhesives that are bio-inspired—notably
the “gecko” nanoadhesives—have become meaningful symbols for
what nanotechnologies can accomplish.
Before looking at bio-inspired adhesives, we should look at
how nanomaterials can yield improvements to existing kinds of
adhesives. Many adhesives are targeted for particular surface types
and others for more general applications. Mechanisms for adhesion
are primarily either mechanical or chemical. Mechanical means
involve the adhesive substance providing a type of interlocking
mechanism, typically by the substance filling small pores in each
of the surfaces. Chemical means are more varied and include direct
chemical bonding and the development of intermolecular forces.
Corresponding to these several mechanisms are various types of
adhesives that have quite different application methods and use
properties. Reactive adhesives, including common two-part epoxies,
provide direct chemical bonding after being applied on thin layers
to a surface and can be quite strong. Light-sensitive adhesives are
cured by exposure to light of specific wavelengths (often ultravioNanoproduct Forms