Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation.
A polymer is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals.
Acrylonitrile butadiene styrene (ABS) (chemical formula (C8H8)x·(C4H6)y·(C3H3N)z ) is a common thermoplastic polymer. Its glass transition temperature is approximately 105 °C (221 °F). ABS is amorphous and therefore has no true melting point.
In materials science and continuum mechanics, viscoelasticity is the property of materials that exhibit both viscous and elastic characteristics when undergoing deformation. Viscous materials, like water, resist shear flow and strain linearly with time when a stress is applied. Elastic materials strain when stretched and immediately return to their original state once the stress is removed.
An elastomer is a polymer with viscoelasticity and with weak intermolecular forces, generally low Young's modulus (E) and high failure strain compared with other materials. The term, a portmanteau of elastic polymer, is often used interchangeably with rubber, although the latter is preferred when referring to vulcanisates. Each of the monomers which link to form the polymer is usually a compound of several elements among carbon, hydrogen, oxygen and silicon. Elastomers are amorphous polymers maintained above their glass transition temperature, so that considerable molecular reconformation is feasible without breaking of covalent bonds. At ambient temperatures, such rubbers are thus relatively compliant and deformable. Their primary uses are for seals, adhesives and molded flexible parts.
Amorphous poly alpha olefin is a commodity chemical used in multiple applications.
An ionomer is a polymer composed of repeat units of both electrically neutral repeating units and ionized units covalently bonded to the polymer backbone as pendant group moieties. Usually no more than 15 mole percent are ionized. The ionized units are often carboxylic acid groups.
Hot-melt adhesive (HMA), also known as hot glue, is a form of thermoplastic adhesive that is commonly sold as solid cylindrical sticks of various diameters designed to be applied using a hot glue gun. The gun uses a continuous-duty heating element to melt the plastic glue, which the user pushes through the gun either with a mechanical trigger mechanism on the gun, or with direct finger pressure. The glue squeezed out of the heated nozzle is initially hot enough to burn and even blister skin. The glue is sticky when hot, and solidifies in a few seconds to one minute. Hot-melt adhesives can also be applied by dipping or spraying, and are popular with hobbyists and crafters both for affixing and as an inexpensive alternative to resin casting.
Membrane roofing is a type of roofing system for buildings, RV's, Ponds and in some cases tanks. It is used to create a watertight covering to protect the interior of a building. Membrane roofs are most commonly made from synthetic rubber, thermoplastic, or modified bitumen. Membrane roofs are most commonly used in commercial application, though they are becoming increasingly common in residential application.
Polybutylene (polybutene-1, poly(1-butene), PB-1) is a polyolefin or saturated polymer with the chemical formula (CH2CH(Et))n. Not be confused with polybutene, PB-1 is mainly used in piping.
Adhesive bonding describes a wafer bonding technique with applying an intermediate layer to connect substrates of different types of materials. Those connections produced can be soluble or insoluble. The commercially available adhesive can be organic or inorganic and is deposited on one or both substrate surfaces. Adhesives, especially the well-established SU-8, and benzocyclobutene (BCB), are specialized for MEMS or electronic component production.
Tackifiers are chemical compounds used in formulating adhesives to increase tack, the stickiness of the surface of the adhesive. They are usually low-molecular weight compounds with high glass transition temperature. At low strain rate, they provide higher stress compliance, and become stiffer at higher strain rates.
Glass frit bonding, also referred to as glass soldering or seal glass bonding, describes a wafer bonding technique with an intermediate glass layer. It is a widely used encapsulation technology for surface micro-machined structures, e.g., accelerometers or gyroscopes. This technique utilizes low melting-point glass and therefore provides various advantages including that viscosity of glass decreases with an increase of temperature. The viscous flow of glass has effects to compensate and planarize surface irregularities, convenient for bonding wafers with a high roughness due to plasma etching or deposition. A low viscosity promotes hermetically sealed encapsulation of structures based on a better adaption of the structured shapes. Further, the coefficient of thermal expansion (CTE) of the glass material is adapted to silicon. This results in low stress in the bonded wafer pair. The glass has to flow and wet the soldered surfaces well below the temperature where deformation or degradation of either of the joined materials or nearby structures occurs. The usual temperature of achieving flowing and wetting is between 450 and 550 °C.
Glue dots are pressure-sensitive adhesive dots, used in various different applications, such as sticking credit cards to paper, arts and crafts, and as a safe adhesive for children to use, without needing a hot glue gun. Glue dots are globules of adhesive, which allow attachments to float above a page. They provide a clean and instant bond and are often a more suitable solution than hot or liquid glues or adhesive tapes. Glue dots leave much less mess, residue, and odor which help present a product in the best way, whilst increasing productivity and reducing costs. Removable glue dots also allow you to create a bond which can be removed when needed.
Pressure-sensitive tape or pressure-sensitive adhesive tape is an adhesive tape that will stick with application of pressure, without the need for a solvent or heat for activation. It is known also in various countries as self-stick tape, sticky tape, or just adhesive tape and tape, as well as genericized trademarks, such as Sellotape, Durex (tape), Scotch tape, etc.
The chemistry of pressure-sensitive adhesives describes the chemical science associated with pressure-sensitive adhesives (PSA). PSA tapes and labels have become an important part of everyday life. These rely on adhesive material affixed to a backing such as paper or plastic film.
Hot melt coating is the application of a layer to a substrate by pre-melting the desired material and then allowing or forcing the material to cool, solidifying the layer. The process is widely used in industry, including pressure-sensitive adhesives, labels, pharmaceuticals, etc.
Acrylonitrile styrene acrylate (ASA), also called acrylic styrene acrylonitrile, is an amorphous thermoplastic developed as an alternative to acrylonitrile butadiene styrene (ABS), that has improved weather resistance. It is an acrylate rubber-modified styrene acrylonitrile copolymer. It is used for general prototyping in 3D printing, where its UV resistance and mechanical properties make it an excellent material for use in fused filament fabrication printers, particularly for outdoor applications. ASA is also widely used in the automotive industry.
Titanium adhesive bonding is an engineering process used in the aerospace industry, medical-device manufacture and elsewhere. Titanium alloy is often used in medical and military applications because of its strength, weight, and corrosion resistance characteristics. In implantable medical devices, titanium is used because of its biocompatibility and its passive, stable oxide layer. Also, titanium allergies are rare and in those cases mitigations like Parylene coating are used. In the aerospace industry titanium is often bonded to save cost, touch times, and the need for mechanical fasteners. In the past, Russian submarines' hulls were completely made of titanium because the non-magnetic nature of the material went undetected by the defense technology at that time. Bonding adhesive to titanium requires preparing the surface beforehand, and there is not a single solution for all applications. For example, etchant and chemical methods are not biocompatible and cannot be employed when the device will come into contact with blood and tissue. Mechanical surface roughness techniques like sanding and laser roughening may make the surface brittle and create micro-hardness regions that would not be suitable for cyclic loading found in military applications. Air oxidation at high temperatures will produce a crystalline oxide layer at a lower investment cost, but the increased temperatures can deform precision parts. The type of adhesive, thermosetting or thermoplastic, and curing methods are also factors in titanium bonding because of the adhesive's interaction with the treated oxide layer. Surface treatments can also be combined. For example, a grit blast process can be followed by a chemical etch and a primer application.
Adhesive bonding is a joining technique used in the manufacture and repair of a wide range of products. Along with welding and soldering, adhesive bonding is one of the basic joining processes. In this technique, components are bonded together using adhesives. The broad range of types of adhesives available allows numerous materials to be bonded together in products as diverse as vehicles, mobile phones, personal care products, buildings, computers and medical devices.
