budownictwo: Silicone

Evidence: 100 • authority: 72

A silicone or polysiloxane is a polymer composed of repeating units of siloxane (−O−SiR2−O−SiR2−, where "R" stands for an organic group). They are typically colorless oils or rubber-like substances. Silicones are used in sealants, adhesives, lubricants, medicine, cooking utensils, thermal insulation, and electrical insulation. Some common forms include silicone oil, grease, rubber, resin, and caulk. From the chemical perspective, silicones are unusual because they feature inorganic backbones, composed only of Si and O, but they have properties of organic polymers. They represent one of the main applications of organosilicon chemistry. Silicone is often confused with one of its constituent e…

Evidence: 64 • authority: 92

The Green Rebirth of Silicone Waste: Recent Advances in Recycling Technologies.. In silicone polymers, more than 90% of the main chain skeletons are linked by Si-O-Si bonds, with organic groups attached to the side chains and terminal groups. These polymers possess both organic and inorganic properties, exhibiting excellent resistance to high and low temperatures, good insulation, and weather resistance. They are widely used in aerospace, biomedical, electrical, transportation sectors and so on. Traditional methods for synthesizing silicones, such as carbon thermal reduction, have led to a sharp increase in global CO 2 emissions. Consequently, developing technologies for the efficient degra…

Evidence: 44 • authority: 92

Chemical Recycling of Silicones-Current State of Play (Building and Construction Focus).. As the demand for silicone polymers continues to grow across various industries, the need for effective recycling methods has become increasingly important, because recycling silicone products reduces landfill waste, conserves resources, and uses less energy. Chemical recycling involves the depolymerization of silicone waste into oligomers, which can then be used to produce virgin-grade silicone. While this sector of the recycling industry is still in its infancy-we estimate that 35,000 to 45,000 metric tons of silicone waste will be chemically recycled worldwide in 2024-an increasing number of compani…

Evidence: 38 • authority: 92

Multifunctional roles and advances of polymers in solar cell technologies: a review.. The integration of polymeric materials into solar cell technologies has emerged as a transformative approach to address the limitations of conventional rigid photovoltaic systems while enabling new functionalities and applications. This comprehensive review examines the multifunctional contributions of polymers across all components of solar cell architectures, from flexible substrates to innovative protective coatings. A critical evaluation of polymer applications reveals significant progress in organic photovoltaics, where donor-acceptor copolymers have enabled power conversion efficiencies (PCEs) exceed…

Evidence: 38 • authority: 72

Inorganic chemistry is the branch of chemistry that studies the preparation, properties, and behavior of inorganic and organometallic compounds. It mainly deals with compounds that are not based on carbon, unlike organic chemistry. However, there is some overlap between inorganic and organic chemistry, especially in organometallic chemistry. Inorganic chemistry is widely used in many areas such as catalysts, materials, paints and pigments, coatings, medicines, fuels, and agriculture.

Evidence: — • authority: 72

In organosilicon chemistry, a siloxane is an organic compound containing a functional group of two silicon atoms bound to an oxygen atom: Si−O−Si. The parent siloxanes include the oligomeric and polymeric hydrides with the formulae H[OSiH2]nOH and [OSiH2]n. Siloxanes also include branched compounds, the defining feature of which is that each pair of silicon centres is separated by one oxygen atom. The siloxane functional group forms the backbone of silicones [−R2Si−O−SiR2−]n, the premier example of which is polydimethylsiloxane (PDMS). The functional group R3SiO− (where the three Rs may be different) is called siloxy. Siloxanes are manmade and have many commercial and industrial application…

Evidence: — • authority: 72

The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or "rubbery" state as the temperature is increased. An amorphous solid that exhibits a glass transition is called a glass. The reverse transition, achieved by supercooling a viscous liquid into the glass state, is called vitrification. The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs (as an experimental definition, typically marked as 100 s of relaxation time). It is always low…

Evidence: — • authority: 72

A polymer () is a substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeating subunits derived from one or more species of monomers. Due to their broad spectrum of properties, both synthetic and natural polymers have 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, produce…

Evidence: — • authority: 72

In polymer chemistry, an inorganic polymer is a polymer with a skeletal structure that does not include carbon atoms in the backbone. Polymers containing inorganic and organic components are sometimes called hybrid polymers, and most so-called inorganic polymers are hybrid polymers. One of the best known examples is polydimethylsiloxane, otherwise known commonly as silicone rubber. Inorganic polymers offer some properties not found in organic materials including low-temperature flexibility, electrical conductivity, and nonflammability. The term inorganic polymer refers generally to one-dimensional polymers, rather than to heavily crosslinked materials such as silicate minerals. Inorganic po…

Evidence: — • authority: 72

In polymer science, the polymer chain or simply backbone of a polymer is the main chain of a polymer. Polymers are often classified according to the elements in the main chains. The character of the backbone, i.e. its flexibility, determines the properties of the polymer (such as the glass transition temperature). For example, in polysiloxanes (silicone), the backbone chain is very flexible, which results in a very low glass transition temperature of −123 °C (−189 °F; 150 K). The polymers with rigid backbones are prone to crystallization (e.g. polythiophenes) in thin films and in solution. Crystallization in its turn affects the optical properties of the polymers, its optical band gap and e…

Evidence: — • authority: 80

Synthesis of some novel silicone-imide hybrid inorganic–organic polymer and their properties

Evidence: — • authority: 88

TRIBOLOGICAL PROPERTIES OF A SILICONE-BASED COMPOSITEWITH INORGANIC ADDITIVES. The paper presents the results of experimental studies, including tribological tests of silicone-based compositeswith additions of hexagonal boron nitride (hBN) and titanium (Ti). The tests were conducted on a BrukerUMT2 tribotester and using a pin-on-disk setup developed by the authors, without a lubricating medium,and they employed a steel ball made of 100Cr6 steel and a sample made of the composite. During the tests,the products were not removed from the contact area. The paper analyzes the influence of additives on thetribological properties of the composite, i.e., the coefficient of friction (COF) as a funct…