Definition

Description: Time needed by a chemical for permeating through a material. An important characteristic, e.g. for gloves, which can be determined. Relevant question for this

Description: A transponder is a transmitting unit with a defined frequency range. It is used for (mainly wireless) communication, displaying or controlling tasks. It receives

Description: Permeation tubes are small, inert tubes containing a chemical compund in its pure form. The chemical is in a two phase equilibrium (either between

Description: Diffusion is the mechanism causing microscopic particles from fluids or gases to spread out freely and evenly within a given volume or through (semi-)permeable

Description: Chemistry means the science dealing with the structure and the behaviour of matter as well as with the according principles. Category:Definition

Description: A polymer is a chemical compund that consists of molecule chains (macromolecules). The process of formation of the chains, i. e. the linking of

Description: Permeation rate is a measurement for the amount of substance (permeate) permeating through a solid within a certain time. The rate indicates the amount

Description: The process called facilitated diffusion takes place when a substance passes through a membrane being conveyed to the other side by a so-called carrier.

Description: Solvents are fluids that are able to contain gases, solids, and other fluids without undergoing chemical reactions. Category:Definition

Description: Composites are materials consisting of several other materials, whereby all technical relevant properties are enhanced during the synthesis. Compounds for composites are mainly polymers,

Description: Technique for permeation rate measurement of a fluid through a film-like polymer. The material of which the permeation rate has to be determined is

Description: Coating that prevents a substance from permeating through a such protected surface. Materials whose permeability is low in genereal are preferred, e.g. aluminium. In

Beschreibung: Norming data sheet dealing with “Plastics – Film and sheeting – determination of the gas transmision rate, part 1: the differential pressure method”. It

Description: Norming data sheet dealing with “Plastics – Film and sheeting – determination of the the thickness by mechanical scanning”. The method is not suitable

Description: Functionalised polymers are chemical compounds composed of molecular chains (macromolecules) with funtionalised side chains. Category:Definition

Description: A substance accelerating normally slow-running chemical or biochemical reactions is called catalyst. The catalyst is never consumed during the reaction so there is always

Description: Collective name for organic acrylic glasses composed of polymethacrylates, which are produced by polymerisation and additional extrusion and injection molding. They feature high transparency

Description: Specific temperature at which amorphous or partly crystalline polymers pass from the solid state into the liquid phase. When reaching the glass transition temperature,

Description: The term “semipermeable” means half diaphanous. It is often used regarding membrane properties and contains the meaning of “selective permeable”. Semipermeability means that a

Description: ISO = International Organisation for Standardisation ISO is a network of the national standards institutes of 156 countries, on the basis of one member

Description: Chemical compounds that produced by chemical methods are called chemicals. They are produced in laboratories, the chemical industry and bioreacors. Category:Definition

Usage: Floor covering, protective sealings, printed circuit boards, canvas, several material grades Category:Definition

Description: During a permeation rate measurement, the retentat is the depleated particle stream that leaves the separated measuring cell (see also: permeat = loaded particle

Description: Fuels are materials emitting technically usable energy while they are burned.Examples for solid fuels: Wood Carbon Nuclear fuels (like uranium or plutonium) Wax Examples

Description: A permeation measurement cell is a testing unit for permeation rate measurements. The actual process of permeation takes place in this cell: The solid

Description: This process means the determining the composition of a certain material (in this case: a polymer) in order to characterise its different properties such

Descpription: An ion is an atom or molecule which carries a positive or a negative charge. The charge is caused by a lack or an

Description: The diffusion coefficient characterises the thermal migration of molecules within a certain material.SI-Unit (m2/s). Category:Definition

Description: Basically, there are two methods usable for seperating gases: separation by membranes (view also: permeability) using membrane contractors whereas the membran itself takes no

Description: A hose consisting of several material layers. The material combination provides optimisation of permeation properties (resp. density) and chemical resistance. Usage: Protective hoses (for

Descpription: The word “hygroscopic” is a technical term used in chemistry and physics. Hygroscopic materials are water-attracting substances. Those substances show the tendency to bind

Description: DIN = German Institute for Standardization (registered association) German institute, responsible for standardisation and developing German Standards. It represents German interests at international and

Description: Fuel cell technology is concerned with developing fuel cells for efficient production of energy. Compared to other energy sources, fuel cells have a very

Description: Multi-layer-foils are thermoplastic plaxtic films composed of two or more combined, different or similar, layers. The layers are put together e.g. by coextrusion or

Description: A polymer blend is a mixture of two or more polymeres. The polymers are mixtured in order to optimise the polymer properties such as

Descpription: Biotechnology is a engineering application of Biology and Biochemistry, including e.g. the process of cloning and the use of genetic engineering in order to

Descpription: The stream of particles migrating through a material during the permeation process is called permeat. Category:Definition

Description: Technology concerned with optimising and developing fuel tanks. The main focus of interest here lies on properties such as density, mobility, (heat and air)

Description: Layer of material, e.g. a polymer or a film, carrying very low permeability for gases, vapors and fluids. Depending on permeation properties, different materials

Description: Radio Frequency Identification (RFID) is a method for contactless reading and saving data. This system was originally developed in order to substitute the identification

Description: In a permeation cell the process of permeation takes place under precisely defined conditions. (Cf. permeation measurement cell) Category:Definition

Description: A solid substance with such a granularity allowing to easily drain the material and causing the grains to hardly be stuck together is called

Description: According to DIN 55958, resins are fluid to solid organic compounds with a typical allocation of molar masses. A distinction is drawn between natural

Descpription: The specific permeability of a material determines the migration rate of another substance through the pores and gaps of the material. The rate depends

Descpription: A membrane is a thin, skin-like seperating layer. In chemistry one uses membranes for separating two environments (in contrast to swinging membranes used in

Description: The permeation coefficient indicates permeability of a solid for a certain substance with respect to a unified thickness. It can be computed by multiplying

Description: Describes temperature dependency of (chemical) reaction speed, given the specific activation energy and the chance of a successful molecule collision. Category:Definition Formula:

Description: The diffusion rate measures the spreading of microscopic particles within fluids or gases through (semi-)permeable barriers. Category:Definition

Beschreibung: Thermoplastics are engineering plastics which are solid at room temperature and which can repeatedly be softened and re-hardened by increasing and decrasing temperature. Category:Definition

Description: Synthetically manufactured, fluid or solid material with all the characteristics of resins defined in DIN 55958 (cf. resin). Synthetical resins are produced from polymerisation

Description: Combinatorial chemistry means the sysnthesis of compounds by taking into account all possible combinations of the reagents. The principle involves reactions with raw material

Description: The catalysis is a chemical reaction involving the presence of a catalyst. A distinction is drawn between homogeneous and heterogeneous catalysis: Homogeneous catalysis means,

Descpription: Energy needed by a system to initiate a particular process, such as diffusion or a chemical reaction. It can be described using the Arrhenius

Description: Polymer blend of actually immiscible polymers, whereby miscibility was reached during the blending process. (Cf. Polymer blend) Category:Definition

Description: The most useful properties of the fluoroploymeres are due to the fluorineatoms, which can be found in the polymerchain. Fluorine is the most electronegative

Description: Plastic which can be transformed into a hard, vitually unmeltable and insoluble product by heating or using other methods. The term “thermoset” comprises both

Title: Non-destructive testing – Terminology – Part 8: Terms used in leak tightness testing; Trilingual version EN 1330-8:1998 Category: Definition Please note: Complete standard sheets

Description: The alloy of gases that is fed as test gas into one half of the permeation measuring cell is called “feed”. Category:Definition

Description: An appropriate way of drying gases is to dry them dynamically. Gases with a very high humidity are pre-dried using high-capacity drying agents. Category:Definition

Description: Permeation measuring means the process of determining the permeation rate of a certain substance. That means measuring, how much of the permeate per time

Description: ASTM = American Society for Testing and Materials Standard development organisation, providing international standards for materials, products, systems, and services. Category:Definition

Description: Barrier Packaging is a packaging with very low permeability for possibly interfering materials (e.g. air). Popular applications e.g. are packagings for food (in order