Chain shuttling polymerization is a process that combines features of both chain-growth and step-growth polymerization mechanisms. This technique allows for the production of polymers with complex architectures and a higher degree of control over molecular weight and distribution compared to traditional polymerization methods. In chain shuttling polymerization, a "shuttling" reagent participates in the polymerization process by cyclically interacting with growing polymer chains.
Chain termination refers to a process in molecular biology and genetics where the synthesis of a nucleic acid (like DNA or RNA) is halted at a specific point during replication or transcription. This can occur in various contexts, and it can involve different mechanisms depending on the biological process in question.
Chain walking is a term that can refer to different concepts depending on the context. In general, it might refer to: 1. **In Exercise or Fitness Context**: Chain walking could refer to a form of exercise that involves walking while using a chain or resistance tool to enhance strength training or endurance activities. 2. **In Engineering or Robotics**: It might describe a method or technique used in robotic movement or mechanisms that involve chains for locomotion.
Chloropolymers are a type of polymer that contains chlorine atoms in their molecular structure. They are typically derived from the polymerization of vinyl chloride or similar monomers containing chlorine. One of the most well-known chloropolymers is poly(vinyl chloride) (PVC), which is widely used in construction, plumbing, electrical insulation, and various consumer goods due to its durability, chemical resistance, and versatility.
As of my last knowledge update in October 2023, Christoph Weder is a prominent figure in the field of mathematics and engineering, particularly known for his work in the area of mathematical optimization and its applications. He may be involved in research, teaching, or specific projects related to these fields.
Coacervates are liquid-phase droplets formed from the spontaneous aggregation of colloidal particles or macromolecules in a solution. These particles typically consist of polymers such as proteins, nucleic acids, or polysaccharides, which can undergo phase separation in certain conditions (e.g., changes in pH, temperature, or ionic strength). Coacervation is a process that can lead to the formation of coacervates and is often categorized into two main types: primary and secondary.
A comonomer is a type of monomer that is used in combination with other monomers to produce a copolymer during a polymerization process. In copolymerization, two or more different types of monomers are linked together to create a polymer with unique properties that may be different from those of the individual homopolymers made from one type of monomer alone.
Compatibilization is a process used in material science and polymer chemistry to improve the compatibility and interaction between two or more immiscible polymers or materials. When two different polymers are blended, they may not mix well due to differences in their chemical structure, polarity, or other physical properties, leading to phase separation and poor mechanical performance. To achieve better dispersion, reduced phase separation, and enhanced properties, compatibilizers are often introduced into the blend.
The "Compendium of Macromolecular Nomenclature" is a reference work that provides standardized names and definitions for macromolecules, including polymers, proteins, and nucleic acids. It serves as a guide to ensure consistency and clarity in the naming of these complex molecules across scientific literature and disciplines.
Condensation polymers are a class of polymers formed through a condensation reaction, where monomer units are linked together, resulting in the release of small molecules, such as water, alcohol, or other simple molecules. This process typically involves the reaction of two different functional groups, such as -OH (hydroxyl) and -NH2 (amine), or -COOH (carboxylic acid) and -OH.
A copolymer is a type of polymer that is made from two or more different monomers (the building blocks of polymers) rather than just one type. The different monomers can be arranged in various ways, leading to different structures and properties in the resulting copolymer. The arrangement can be random, alternating, block, or grafted, among other configurations.
The Cossee–Arlman mechanism is a theoretical framework used to explain the mechanism of polymerization in certain catalytic processes, particularly in the context of olefin polymerization. It was proposed by the chemists Cossee and Arlman in the mid-20th century. The mechanism describes the coordinated steps involved in the polymerization of alkenes (olefins) through a transition metal catalyst, typically zirconium or other metal complexes.
A cross-link refers to a bond or connection that links one polymer chain to another, typically forming a three-dimensional network. Cross-linking can occur in various materials, including plastics, gels, and biological molecules such as proteins and DNA. In a broader context, cross-links can also refer to links that connect different sections of a website or different documents, facilitating navigation and information retrieval.
In chemistry, "curing" refers to a process in which a material, often a polymer or resin, is hardened or set through a chemical reaction. This process typically involves the addition of a curing agent, heat, or ultraviolet (UV) light to initiate a cross-linking reaction, which transforms the initially soft or liquid material into a solid, durable structure.
Cyclic olefin copolymers (COCs) are a class of thermoplastic polymers that are derived from the polymerization of cyclic olefin monomers. These materials are known for their unique combination of properties, which include high transparency, low moisture absorption, excellent chemical resistance, and good mechanical strength. COCs typically have a low density and can be molded easily into various shapes, making them suitable for a wide range of applications.
David Henry Solomon is an American banker known for his role as the CEO of Goldman Sachs, a leading global investment banking, securities, and investment management firm. He has been with Goldman Sachs for a significant portion of his career, having joined the firm in 1999. Before becoming CEO, Solomon held various leadership positions, including serving as the president and chief operating officer. He assumed the role of CEO in October 2018, succeeding Lloyd Blankfein.
The degree of polymerization (DP) is a measure that indicates the number of repeating units in a polymer chain. It is essentially the number of monomeric units that are joined together to form a larger polymer molecule. The DP can provide insights into the properties of the polymer, such as its molecular weight, physical characteristics, and performance in applications.
Dentine bonding agents are specialized materials used in dentistry to bond restorative materials, such as composites, to the dentine layer of the tooth structure. Dentine is the layer beneath the enamel that provides support and structure to the tooth. The bonding of materials to dentine is crucial for the long-term success of dental restorations, as it helps to create a seal that prevents microleakage and enhances the overall durability of the restoration.
Die swell is a phenomenon that occurs during the processing of polymers, especially during extrusion. When a molten polymer is forced through a die to take a specific shape (such as in the production of pipes, sheets, or films), it often expands or swells as it exits the die. This swelling is primarily due to the relaxation of the polymer chains as they leave the constraints of the die.
Dispersity is a term that can refer to the degree or measure of how dispersed or spread out a set of data points or elements is within a particular space or dataset. It often applies in various fields, such as statistics, ecology, economics, and social sciences, to describe the distribution and variation among entities. In a statistical context, dispersity may relate to measures like variance, standard deviation, or range, which indicate how much variation exists from the average or mean value of a dataset.