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Expandable Microsphere
Expandable microspheres are microscopic spheres comprising a thermoplastic shell encapsulating a low boiling point liquid hydrocarbon. When heated to a temperature high enough to soften the thermoplastic shell, the increasing pressure of the hydrocarbon will cause the microsphere to expand. The volume can increase by 60 to 80 times. Expandable microsphere The expandable microsphere is a material that can act as a blowing agent when mixed in a product and subsequently heated to cause expansion within the matrix. The expandable microspheres are off-white, can be 6 to 40 micrometers in average diameter and have a density of 900 to 1400 kg/m3. The expandable microspheres are used as a blowing agent in products like e.g. puff ink, automotive underbody coatings or injection molding of thermoplastics."New developments with expandable microspheres", Klas Elfving, Expancel. The Fifth International Conference Blowing agents and Foaming Processes 2003, Rapra. Here the product must be heated at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoplastic
A thermoplastic, or thermosoftening plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling. Most thermoplastics have a high molecular weight. The polymer chains associate by intermolecular forces, which weaken rapidly with increased temperature, yielding a viscous liquid. In this state, thermoplastics may be reshaped, and are typically used to produce parts by various polymer processing techniques such as injection molding, compression molding, calendering, and extrusion. Thermoplastics differ from thermosetting polymers (or "thermosets"), which form irreversible chemical bonds during the curing process. Thermosets do not melt when heated, but typically decompose and do not reform upon cooling. Above its glass transition temperature and below its melting point, the physical properties of a thermoplastic change drastically without an associated phase change. Some thermoplastics do not fully ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually faint, and may be similar to that of gasoline or Naphtha, lighter fluid. They occur in a diverse range of molecular structures and phases: they can be gases (such as methane and propane), liquids (such as hexane and benzene), low melting solids (such as paraffin wax and naphthalene) or polymers (such as polyethylene and polystyrene). In the fossil fuel industries, ''hydrocarbon'' refers to naturally occurring petroleum, natural gas and coal, or their hydrocarbon derivatives and purified forms. Combustion of hydrocarbons is the main source of the world's energy. Petroleum is the dominant raw-material source for organic commodity chemicals such as solvents and polymers. Most anthropogenic (human-generated) emissions of greenhouse gases are eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cultured Marble
Engineered stone is a composite material made of crushed stone bound together by an adhesive to create a solid surface. The adhesive is most commonly polymer resin, with some newer versions using cement mix. This category includes engineered quartz (SiO2), polymer concrete and engineered marble stone. The application of these products depends on the original stone used. For engineered marbles the most common application is indoor flooring and walls, while the quartz based product is used primarily for kitchen countertops as an alternative to laminate or granite. Related materials include geopolymers and cast stone. Unlike terrazzo, the material is factory made in either blocks or slabs, cut and polished by fabricators, and assembled at the worksite. Engineered stone is also commonly referred to as agglomerate or agglomerated stone, the last term being that recognised by European Standards (EN 14618), although to add to the terminological confusion, this standard also includes mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint Compound
Joint compound (also known as drywall compound, drywall mud, joint cement or mastic) is a white powder of primarily gypsum dust mixed with water to form a paste the consistency of cake frosting, which is spread onto drywall and sanded when dry to create a seamless base for paint on walls and ceilings. When used for new walls, joint compound effectively eliminates blemishes from the surface of drywall, such as fasteners, damage, or drywall tape. Joint compound is used to finish gypsum panel joints filled with paper or fiber ''joint tape,'' corner bead, trim and fasteners, and to skim coat. It is also convenient for patching holes, bumps, tears, and other minor damage to existing walls. In North America, troweling joint mud on gypsum panels is a standard construction technique prior to painting wall and ceiling surfaces. Joint compound type and formula selection forms part of a drywall system that can be finished anywhere from a level 0 to a level 5, where 0 is not finished in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenosphere
A cenosphere or kenosphere is a lightweight, inert, hollow sphere made largely of silica and alumina and filled with air or inert gas, typically produced as a coal combustion byproduct at thermal power plants. The color of cenospheres varies from gray to almost white and their density is about , which gives them a great buoyancy. Cenospheres are hard and rigid, light, waterproof and insulative. This makes them highly useful in a variety of products, notably fillers. Etymology The word ''cenosphere'' or ''kenosphere'' is derived from two Greek words, ''κενός'' (''kenos'': hollow, empty) and ''σφαίρα'' (''sphaira'': sphere), literally meaning "hollow sphere." Production The process of burning coal in thermal power plants produces fly ash containing ceramic particles made largely of alumina and silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass Microsphere
Glass microspheres are microscopic spheres of glass manufactured for a wide variety of uses in research, medicine, consumer goods and various industries. Glass microspheres are usually between 1 and 1000 micrometers in diameter, although the sizes can range from 100 nanometers to 5 millimeters in diameter. Hollow glass microspheres, sometimes termed microballoons or glass bubbles, have diameters ranging from 10 to 300 micrometers. Hollow spheres are used as a lightweight filler in composite materials such as syntactic foam and lightweight concrete. Microballoons give syntactic foam its light weight, low thermal conductivity, and a resistance to compressive stress that far exceeds that of other foams. These properties are exploited in the hulls of submersibles and deep-sea oil drilling equipment, where other types of foam would implode. Hollow spheres of other materials create syntactic foams with different properties: ceramic balloons e.g. can make a light syntactic alumini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microbead
Microbeads are manufactured solid plastic particles of less than one millimeter in their largest dimension. They are most frequently made of polyethylene but can be of other petrochemical plastics such as polypropylene and polystyrene. They are used in exfoliating personal care products, toothpastes, and in biomedical and health-science research. Microbeads can cause plastic particle water pollution and pose an environmental hazard for aquatic animals in freshwater and ocean water. In the United States, the Microbead-Free Waters Act of 2015 phased out microbeads in rinse-off cosmetics by July 2017. Several other countries have also banned microbeads from rinse-off cosmetics, including Canada, France, New Zealand, Sweden, Taiwan, and the United Kingdom. Types Microbeads are manufactured solid plastic particles of less than one millimeter in their largest dimension when they are first created, and are typically created using material such as polyethylene (PE), polyethylene ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microplastics
Microplastics are "synthetic solid particles or polymeric matrices, with regular or irregular shape and with size ranging from 1 μm to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water." Microplastics are dangerous to human health and the environment because they contain harmful chemicals which leak into the air, water, and food. Microplastics cause pollution by entering natural ecosystems from a variety of sources, including cosmetics, clothing, construction, renovation, food packaging, and industrial processes. The term ''microplastics'' is used to differentiate from larger, non-microscopic plastic waste. Two classifications of microplastics are currently recognized. Primary microplastics include any plastic fragments or particles that are already 5.0 mm in size or less before entering the environment. These include microfibers from clothing, microbeads, plastic glitter and plastic pellets (also known as nurdles). Seconda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastic Particle Water Pollution
Plastic pellet pollution is a type of marine debris originating from the plastic particles that are universally used to manufacture large-scale plastics. In the context of plastic pollution, these pre-production plastic pellets are sometimes known as "nurdles". These microplastics are created separately from the user plastics they are melted down to form, and pellet loss can occur during both the manufacturing and transport stages. When released into the open environment, they create persistent pollution both in the oceans and on beaches. About 230,000 tonnes of nurdles are thought to be deposited in the oceans each year, where they are often mistaken for food by seabirds, fish and other wildlife. Due to their small size, they are notoriously difficult to clear up from beaches and elsewhere. Description Nurdles are the second largest source of microplastics in the ocean. Approximately 27 million tonnes (60 billion pounds) of nurdles are manufactured annually in the Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoplastics
A thermoplastic, or thermosoftening plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling. Most thermoplastics have a high molecular weight. The polymer chains associate by intermolecular forces, which weaken rapidly with increased temperature, yielding a viscous liquid. In this state, thermoplastics may be reshaped, and are typically used to produce parts by various polymer processing techniques such as injection molding, compression molding, calendering, and extrusion. Thermoplastics differ from thermosetting polymers (or "thermosets"), which form irreversible chemical bonds during the curing process. Thermosets do not melt when heated, but typically decompose and do not reform upon cooling. Above its glass transition temperature and below its melting point, the physical properties of a thermoplastic change drastically without an associated phase change. Some thermoplastics do not full ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
