Waterproofers & Water Sealers
Include products that are added to concrete and plaster (mortar) to waterproof the structure.
Concrete admixtures (plasticiser)
Are products added in concrete so as to change the property of concrete to our desired requirement.
Grouts and grouting compounds
Are products added in concrete so as to change the property of concrete to our desired requirement.
Capsules for anchoring/bolting
Provides unique fast setting method of bonding and anchoring bolts into rocks for heavy machinery fixing, tunnel lining.
Protective coating & impregnations
Are products which get impregnated into the surface on which they are applied and thus help in water proofing.
Construction Aid
They include products which are used for easy removal of shutters and curing of concrete.
Floor hardners
Help to make the floor tough and hard wearing.
Waterproof Coating/ Membrane (plasticiser)
Include products for waterproofing coating & membrane.
Sealants
Are used to form long lasting weather resistant and waterproofing seals in joints.
Shortcrete products
Are used for sprayed concrete and mortar.
Repair compounds
Are used for bonding and Repair works.
Tile & Structural Adhesive
Excellent bonding for ceramic, mosaic, marble &granite tiles to concrete / brick surfaces.
Saturday, April 3, 2010
Monday, February 18, 2008
various drilling fluids
Emulsion Drilling Fluids
A dispersion of one immiscible liquid into another through the use of a chemical that reduces the interfacial tension between the two liquids to achieve stability. Two emulsion types are used as muds: (1) oil-in-water (or direct) emulsion, known as an "emulsion mud" and (2) water-in-oil (or invert) emulsion, known as an "invert emulsion mud." The former is classified as a water-base mud and the latter as an oil-base mud.
Production Enhancement
A type of damage in which there is a combination of two or more immiscible fluids, including gas, that will not separate into individual components. Emulsions can form when fluid filtrates or injected fluids and reservoir fluids (for example oil or brine) mix, or when the pH of the producing fluid changes, such as after an acidizing treatment. Acidizing might change the pH from 6 or 7 to less than 4. Emulsions are normally found in gravel packs and perforations, or inside the formation.
Most emulsions break easily when the source of the mixing energy is removed. However, some natural and artificial stabilizing agents, such as surfactants and small particle solids, keep fluids emulsified. Natural surfactants, created by bacteria or during the oil generation process, can be found in many waters and crude oils, while artificial surfactants are part of many drilling, completion or stimulation fluids. Among the most common solids that stabilize emulsions are iron sulfide, paraffin, sand, silt, clay, asphalt, scale and corrosion products.
Emulsions are typically treated using mutual solvents.
Heavy Oil
A dispersion of droplets of one liquid in another liquid with which it is incompletely miscible. Emulsions can form in heavy oils that contain a significant amount of asphaltenes. The asphaltenes act as surfactants with formation or treatment water. The resulting emulsion droplets have high-energy bonds creating a very tight dispersion of droplets that is not easily separated. These surface-acting forces can create both oil-in-water and/or water-in-oil emulsions. Such emulsions require temperature and chemical treating in surface equipment in order to separate.
Sediment Geology
The unconsolidated grains of minerals, organic matter or preexisting rocks, that can be transported by water, ice or wind, and deposited. The processes by which sediment forms and is transported occur at or near the surface of the Earth and at relatively low pressures and temperatures. Sedimentary rocks form from the accumulation and lithification of sediment. Sediments are classified according to size by the Udden-Wentworth scale.
Appraisal Geology
The phase of petroleum operations that immediately follows successful exploratory drilling. During appraisal, delineation wells might be drilled to determine the size of the oil or gas field and how to develop it most efficiently.
Exploration Geology
The initial phase in petroleum operations that includes generation of a prospect or play or both, and drilling of an exploration well. Appraisal, development and production phases follow successful exploration.
Saturday, February 16, 2008
VARIOUS CHEMICALS, ADDITIVES USED IN PROCESSING OF OIL&GAS
Dewatering aid
The use of Dewatering Aid for crude oil stored in tanks demonstrates excellent water and salt removal from crude. Tankage dehydration as it is commonly termed enhances desalting efficiency. Increased profitability results from reduced corrosion and fouling of downstream equipments.
Refineries processing opportunity crude slates containing higher filterable solids and BS&W result in frequent desalter upsets as well as exchanger fouling. Slop oils containing high level of solids also contribute to such upsets. desalting programs offer excellent dehydration; superior salt & solids removal with over 90% efficiencies and reduced oil undercarry. Increased profitability results from reduced fouling and lower cost of oil recovery from brine.
Condensing corrosive gaseous species like HCl, H2S and H2CO3 create a highly corrosive low pH environment in the crude unit overhead system. dual chemical program consisting of neutralizer and filming corrosion inhibitor, injected into the overhead system and reflux line ensure superior corrosion control and reliability of the equipment.
Crude preheat exchanger train and furnace fouling can significantly reduce unit throughput and increase processing costs. Foulant precursors range from scale solids to asphaltene deposition and oxidative polymerization. effective fouling control programs injected into desalted crude provide longer unit run lengths. Improved levels of heat transfer lead to increased profits through higher feed rates and lower fuel costs.
Low pH due to acid gas condensation in vacuum overhead system results in severe corrosion. An effective neutralizing amine provides good pH control, thus effectively reducing corrosion rates, resulting in less downtime, maintenance, and operational problems.
effective corrosion control program in the FCCU main fractionator column & gas plant corrosion prevents hydrogen blistering and sulfidic corrosion attack. Fractionator and stabilizer reboiler fouling is thus significantly reduced resulting in increased efficiency and profitability.
FCC Slurry Exchanger Fouling Control Program
FCC slurry fouling due to catalyst fines and asphaltene deposition result in fouling on steam generation equipment and preheat exchangers. effective fouling control program offers excellent Return on Investment (ROI. Through enhanced levels of heat transfer through exchangers and improved quenching efficiency in the main fractionator.
Delayed Coker Foam Control
A good fouling control program increases the run length of furnaces in these units reducing fuel consumption and decoking frequency. delayed coker and visbreaker corrosion control programs provide increased tube life and enhanced reliability of the system.
Delayed Coker and Visbreaker Corrosion Control Program
Coke drum foaming due to entrained hydrocarbon causes carry over of coke fines to the main fractionator leading to fouling of transfer lines and the main fractionator. Our antifoam with superior foam killing efficiency helps to increase coker throughput and increase profitability.
H2S Scavengers
H2S scavengers help in doctoring fuels for odor. They forage for H2S and convert mercaptans to disulfides. These products are useful in eliminating the risk of exposure to harmful gases in the work environment. They also help refiners in meeting copper corrosion specifications.
Tank Cleaning Chemicals
Heavy crudes stored in tanks commonly have sludge deposition occurring at the base of the tanks. These deposits when left untreated, cause tank hold-up, occupy much of tankage space and also contribute to disturbances in operation due to high BS &W and sludge carryover. Quite some oil is also lost in the process of removal of this sludge through normal cleaning procedures. Our tank cleaning chemicals help the refiner treat sludge deposits thereby freeing up the tankage space and generate significant savings in processing costs through crude oil recovery.
Abbreviation for Basic Sediment and Water. BS&W is measured from a liquid sample of the production stream. It includes free water, sediment and emulsion and is measured as a volume percentage of the production stream.
Wednesday, February 13, 2008
METHANOL PRODUCTION
METHANOL PLANT WITH LURGI REACTORS
Capacity: 1500 TPD
Status: Installed Upgrades: Upgraded in 1976, when (2) Lurgi reactors were added Brief Overview:
1500 TPD, methanol plant. Unit has Selas reformer, that feeds a common compression and methanol converter reaction system. Upgraded in 1976 with (2) Lurgi reactors. Main components include a Clark compressors, GE turbines, SS and Adm Brass condensors and exchangers.
Process Description:
SELAS PROCESS FEED SYSTEM
Methanol cannot be synthesized (or converted) from natural gas directly in the Bishop process. The components of natural gas (methane, ethane, propane, etc.) must first be converted into intermediate compounds before they can then be synthesized into methanol in the Lurgi converters. The process used to form these intermediate compounds (carbon monoxide, carbon dioxide, and hydrogen) is steam reforming. Since the reforming reaction is endothermic (requires heat to sustain it), the reaction is carried out in what is termed a primary reformer which is actually a fired furnace. Natural gas-fired burners provide heat to the Selas Reformer. Since sulfur is a reformer catalyst poison, a desulfurizing system is in place to "scrub" the incoming natural gas for process feed. Two vessels filled with activated carbon are operated in series, and a third vessel contains zinc oxide. This scrubbing system removes primarily hydrogen sulfide (H2S).
The process feed to the Selas Reformer is a mixture of 240 psig steam, "scrubbed" natural gas, and (at times) gaseous carbon dioxide. The carbon dioxide (CO2) is vaporized from liquid CO2 held in refrigerated storage tanks. The ratio of process steam to the carbon components of the process feed is called the steam to carbon ratio. This is controlled to prevent the formation of elemental carbon in the reformer tubes. This can result when insufficient oxygen (available in the steam, water) is present in the reforming reaction.
The process gas is passed through reformer tubes filled with a nickel in an aluminum-oxide base catalyst. The resulting product is a mixture (primarily) of hydrogen, carbon monoxide, carbon dioxide, and water. This is called "reformed gas." The reformed gas from the Selas Reformer passes through two waste heat boilers, a boiler feed water preheater, a set of fin fans, a knock out pot, trim cooler, knock out pot, and then to the suction of the Booster compressor.
The steam and natural gas are on flow ratio control (steam to carbon ratio). Both the steam and natural gas flows are temperature and pressure compensated. The ratio controller is tied into the reformer shutdown system.
SELAS FIRING
The reforming reaction is endothermic or requires heat to sustain it. The Selas Reformer is a side-fired furnace with downflow in the process tubes. Natural gas-fired burners provide heat to the Selas Reformer, and an induced draft (ID) fan pulls combustion air into the firebox through openings in the burner assembly. The furnace is divided into two sections, east and west. Each section contains ninety catalyst filled tubes (4 1/2 in. X 40 ft.) in two staggered rows. There are eight rows of burners on the east and west side of each section, with each row containing twenty-four duradiant burners (768 total burners).
The combustion gas from each section goes into a common flue gas duct at the top of the furnace. The flue gas goes through a preheater section where the inlet process gas is preheated to reduce the heat load needed on the reformer tubes. After the preheater, is the steam superheater (HE-1984) where steam generated in the process waste heat recovery boilers downstream is superheated. The flue gas then goes through the induced draft fan (C-176) and then joins with the exhaust gas from the G.E. gas turbine. The combined flue gases then go to the economizer (HE-2607) where boiler feed water to all the waste heat boilers is preheated. After the economizer (HE-2607), the flue gases are ducted to the 240# steam boiler (HE-2728) and the BFW economizer (HE-2729).
SELAS WASTE HEAT BOILERS
The Selas waste heat recovery system serves two purposes. The process gas out of the Selas is approximately 1,575 F. Therefore, the primary purpose is to reduce this temperature to cause the water to separate from the reformed gas. This water is recovered in knock out pots and put into the process condensate system where it will be treated and put into the MS II Unit boiler feed water system. The second purpose of the heat recovery system is to heat up the boiler feed water needed to generate steam to operate equipment throughout the unit as well as to supply steam export to the Boilerhouse. This preheated boiler feed water is used in the MS I Area and the rest is returned to the Boilerhouse. Preheated boiler feed water is used in order to reduce the heat load required to produce steam.
The Selas waste heat recovery system utilizes heat from the reformed gas to preheat the Boiler Feed Water and produce steam. As the reformed gas is cooled from approximately 1,575 0F to 1000 F, water is removed via knock out pots. The condensate is collected in the unit process condensate system where it is treated and used in the MS II Area for boiler feed water. Preheated boiler feed water from the Selas Area is used in the MS I Area and the rest is returned for use at the Boilerhouse. Preheated boiler feed water reduces the heat required to produce steam. The steam generated is used in the unit and the excess is exported to the plant.
The waste heat recovery system consists of the following: HE-1542, HE-2955, HE-2607, HE-2551 (boiler feed water heat exchangers), HE-2728 (240 psig boiler), HE-2954, HE-1470, HE-1790, and HE-1501 (600 psig boiler), and HE-1984 (600 psig steam superheater).
SELAS PRECOOLING BOOSTER COMPRESSOR
Reformed gas is delivered to the Booster compressor, C-327, at 104 F and 105 psig after being cooled in the waste heat recovery section of the Selas Reformer.
The reformed gas from the Selas Reformer goes through two waste heat boilers, a boiler feed water preheater, a set of fin fans, knock out pot, trim cooler, knock out pot, and then to the suction of the Booster compressor (C-327). After the Booster compressor, the heat generated in compression must be removed by means of a boiler feed water heat exchanger, fin fans, trim cooler, a knock out pot, and then to the Make-Up Gas (MUG) compressor suction.
The speed of C-327 is controlled by a pressure controller (PIC-204) which adjusts the governor on the compressor driver, PT-1220, to maintain a constant suction pressure to the compressor. This allows the compressor to compensate for small to moderate changes in the Selas reformed gas flow and still maintain a constant backpressure on the Selas Reformer. In order to prevent surging from occurring, a certain minimum flow must be supplied to the compressor suction. This is accomplished by a flow-controlled bypass (antisurge valve PDIC-203) from the discharge of C-327 back to its suction upstream of the cooling equipment. The compressor, in this manner, pumps enough gas to avoid the combination of conditions that could allow it to surge.
MAKE-UP GAS (MUG) COMPRESSION PROCESS DESCRIPTION
PROCESS GAS TO MUG
The combining of process gas and process steam and passing it through catalyst-filled tubes while heating them externally at high temperatures will result in reformed gas. Reformed gas is composed primarily of hydrogen, carbon dioxide, and carbon monoxide. Once the reformed gas exits the Selas Reformer, the objective is to lower the temperature of the reformed gas and remove water saturating the reformed gas. This objective has to be completed before the reformed gas from the Selas Reformer flows into the suction first stage of the MUG (C-328). In order to cool the reformed gas, it flows through a series of heat exchangers, fin fans, waste heat boilers, and water knock out vessels.
The reformed gas flows through the shell while methanol flows through the tubes which is acting as heat for the finishing column (T-288). This process helps reduce the cost of using 40# steam to heat up T-288. The reformed gas then flows into the waste heat reboiler knock out vessel (V-2353) where some hot condensate is separated from the reformed gas. The condensate now becomes process condensate that flows to the decarbonator (T-334) in preparation for the deaerator (V-2364) to be used as BFW. The overhead of V-2353 is reformed gas that flows to two heat exchangers fixed side by side, HE-2541 and HE-2780. In the purge gas preheater (HE-2541) reformed gas flows through the tubes and purge gas from the Lurgi loop to the expanders flows on the shell side. The purge gas firing preheater (HE-2780) has reformed gas on the tube side and purge gas on the shell side. The purge gas from the expanders is being preheated for the Davy Reformer to be used for firing fuel in the furnace. The reformed gas flow then goes to the reformed gas air cooler (HE-2545) which is made of ten fin fans.
MS UNIT LURGI AREA PROCESS DESCRIPTION
LURGI CONVERTERS
The purpose of the Lurgi converter loop is to produce methanol using synthesis gas as the raw material. Synthesis gas from the discharge of the MUG compressor (C-328) is combined with synthesis gas from the high pressure separator (V-2359) at the suction of the recycle compressor (C-329). The discharge pressure of C-329 is controlled at approximately 846 psig.
The discharge flow from C-329 is preheated in interchanger HE-2553 (shell side) and fed to the two converters (V-2357 and V-2358) which are operated in parallel. The synthesis gas flows through the tubes of the converters, which are filled with a pellet-shaped catalyst. This catalyst is zinc/copper in an aluminum oxide base. The product is a gas stream containing methanol and synthesis gas, which was not converted due to catalyst efficiency.
MS UNIT PURIFICATION AREA PROCESS DESCRIPTION
"A" TRAIN PURIFICATION (T-280 & T-92)
The purpose of T-280 is to purify crude methanol to sales grade specification. This is done by reducing the concentration of water, ethanol and light ends.
Crude methanol feed to T-280 is preheated in HE-2557 and HE-2569. Preheating the feed reduces the amount of steam required to maintain the columns temperature profile. To control internal corrision of the column, caustic is added to the feed to maintain a pH of 10. Samples of the residue flow are taken and analyzed for pH concentrations.
The sales grade methanol is removed from the upper portion of the tower at tray 56 as a sidestream flow via HE-2558 and HE-1927 and is sent to the rundown storage vessels. The overhead vapors taken off from the top of T-280 are condensed as they pass through a series of fin fan air coolers and heat exchangers. The condensed liquid is then fed back to T-280 at tray 60 as reflux. T-280 O.H. receiver (V-1387) non-condensable vapors are taken off the top of V-1387 via the "A" train DME compressor and sent via the burn line to the Boilerhouse as firing fuel. The ethanol and other impurities are removed from T-280 by means of an upper draw off locaated at trays 26 & 30 and from a lower draw off located at trays 5 & 7, this drawn off material is sent to the MO grade storage vessel (V-323). The water removed from T-280 base as a residue flow, is pumped to T-92. At T-92 methanol is stripped from the residue streams from T-280 and T-288. The overhead vapor either directed into T-280 when in operation or to T-288 which is in continious opertation as T-92. The hot residue flow from T-92 is pumped through HE-2557 and HE-2569 to preheat the methanol feed for T-280 and T-288. The T-92 residue flow then goes to the Waste Water Treatment Plant (WWTP).
T-279 DEGASIFIER
The purpose of T-279 is to remove dissolved gases in the crude methanol liquid from the low pressure separator (V-2360). The methanol liquid exits the low pressure separator (V-2360) at approximately 90 psi. The methanol from V-2360 flows to T-279 as feed via LCV-608. T-279 pressure is controlled by "A" Train DME Compressor (C-256) suction at approximately 5.0 psi. As the crude methanol liquid enters T-279, saturated gases flash overhead into V-1386 where the liquid is batched back into T-279 base. The gases in V-1386 go overhead through cooling water exchanger HE-1490 to further condense any remaining liquid in the gas before it enters the "A" train DME compressor (C-256) suction liquid knock out vessel. The overhead gas from V-2469 enters the C-256 suction at approximately 5.0 psi and is compressed to approximately 25 psi before entering the low pressure purge gas line that serves as boiler fuel to the main Boilerhouse. The liquid from V-2469 is pumped to MO grade methanol storage vessel V-323 with the base of T-279, or the flow can be diverted to T-279 along with T-280 and T-288 side draws.
T-288 PURIFICATION COLUMN
The purpose of T-288 is to purify crude methanol to sales grade specification. This is done by reducing the concentration of water, ethanol and light ends. Crude methanol is fed to T-288 after it has been preheated in HE-2557 and HE-2569. This helps to reduce the required steam for the tower. T-288 has two waste heat reboilers, HE-2539 and HE-2540, that receive their heat from hot DPG reformed gas, and are able to supply approximately 64% of the normal reboiler requirements. Steam reboiler HE-2578, which uses 40# steam, is used as a trim reboiler to supply the remaining 32% of the heat. HE-2578 is sized to handle the full distillation required if reformed gas is not available.
Caustic is added to the feed (preheated crude methanol) to reduce corrosion in the tower. This caustic flow is added to maintain a 10 pH in the tower residue stream. The sales grade methanol is removed from the upper portion of the tower (at trays 70, 72, 74 & 76) as a sidestream flow and sent to the rundown storage vessels (V-1390, V-1391 & V-1392). The overhead vapor is taken off the top of T-288 and condensed in the overhead condensers (HE-1575 & HE-1576) and sent to the overhead receiver V-104. The liquid in V-104 is fed back to T-288 as reflux (at tray 79). The noncondensables in V-104 are taken off the top of the vessel via the "B" train DME compressor (C-332) and sent to the Boilerhouse to be used as fuel.
The ethanol and other impurities are removed from the side of T-288 by means of an upper draw-off (at trays 22, 26, 30 & 36) and a lower draw-off (at trays 6 ,8 & 10) and are sent to the MO grade storage vessel, V-323. The water is removed from the base of T-288 as a residue flow is sent to T-92. At T-92 methanol is stripped from the residue streams from T-280 and T-288. The overhead vapor either directed into T-280 when in operation or to T-288 which is in continious opertation as T-92. The hot residue flow from T-92 is pumped through HE-2557 and HE-2569 to preheat the methanol feed for T-280 and T-288. The T-92 residue flow then goes to the Waste Water Treatment Plant (WWTP).
Tuesday, February 12, 2008
MASTERBATCH
MASTERBATCH
A homogeneous mixture of Masterbatch is a concentrated mixture of pigments and/or additives encapsulated during a heat process into a carrier resin which is then cooled and cut into a granular shape. Masterbatches are used to improve dispersion of reinforcing agents, improve breakdown of the rubber, lower the heat history of a compound or facilitate the weighing or dispersion of small amounts of additives.
§ Production of masterbatches which contain short fibres or pulps.
§ masterbatches, the coloring and special function imparting agents in plastics.
§ The ability of a color masterbatches to mix into the polymer varies depending upon its viscosity and flow.
Master batch products are separated into two major types.
· The pigment master batch to color the plastic.
· The functional additive master batches make the plastic capable of certain performances like making them heat resistant, weather resistant etc. Some of the functional master batches are UV Masterbatch, antifog agents, antiblock agents, antistatic agents, etc.
The best RAW MATERIALS for MASTERBATCH
for black masterbatch, only the best quality carbon black powder from renowned carbon black manufacturer is used. Similarly for White Masterbatch we import and use the the best quality of Titanium Dioxide and Additives.
Red oxide for red color and thiylocynin for green and yellow.
Monday, February 11, 2008
GLOSSRY FOR PLASTIC/RUBBER INDUSTRIES
Glossary
additive: any substance added to polymers to improve or modify one or more properties.
antiblock: an additive incorporated in or applied to plastic films to prevent the unintentional adherence during production, storage or use
antioxidant: an additive that inhibits or retards oxidation during production, processing, storage and use
antistatic agent: an additive which imparts a degree of electrical conductivity to plastics, allowing for the dissipation of static electricity.
calcium carbonate: widely used inorganic filler (calcite, chalk, marble and limestone)
carbon black: the most widely used black pigment, also acting as a UV stabiliser in plastics.
carrier: an inert polymer in which the active ingredients of a masterbatch are compounded
chalking: a dry, chalk-like appearance or deposit on the surface of a plastic
clarifier: an additive added to semi-crystalline polymers to modify their crystalline structure by providing sites for initiation of crystallisation, enhancing clarity, hardness, and tensile strength
compatibility: a state in which a component of an admixture in plastics will not exude, bloom, or separate
compound: the intimate admixing of a polymer or polymers with other ingredients such as fillers, plasticisers, catalysts and colorants
copolymer: a polymer derived from more than one species of monomer
cross-linking: the process of multiple intermolecular bonding between polymeric chains
density: weight per unit volume of a substance, usually reported in g/cc or kg/m³.
die: a steel block containing an orifice through which plastic material is extruded, thus shaping it to the desired form.
discoloration: a colour change which involves either lightening or darkening and/or change in hue
dispersion: a heterogeneous system in which a finely divided material is distributed homogeneously in an other material
dye: a colorant, usually transparent, which is soluble in the application medium
extender: an inert substance added to a polymer to reduce its cost
extruder: a machine for the continuous shaping of a moulding material through a die in the form of strands, films, fibres, pipes, sheets, profiles, etc.
filler: a solid, relatively inert, material added to a plastic in order to modify its strength, permanence, working properties, or other qualities or reduce their cost
film: a thin plane product of arbitrarily limited thickness, in which the thickness is very small in proportion to length and width
flame retardant: an additive which renders a polymer fire-resistant
flexography: a printing method in which a liquid ink is applied to a raised photopolymer or rubber plate (stereo) in contact with an inking (anilox) roller. the plate rotates and transfers the image to the surface of the substrate.
fluorescent colorant: a colorant that absorbs light as particular portions of the colour spectrum, re-emitting this light energy at much lower frequencies or longer wavelengths.
gloss: the degree to which a surface approaches perfect optical smoothness in its capacity to reflect light gravure printing: a printing process by which the depressions in an engraved roll are filled with ink, the excess being wiped off by a doctor blade. ink remaining in the depressions is deposited on a flexible film as it passes between the engraved roll and the back-up roll
haze: a cloudy appearance within or on the surface of a plastic
kLy: kilo-Langley is a unit of incident radiation energy (1 kLy = 1 kcal cm-2)
light fastness: resistance to colour changes due to exposure to light without direct atmospheric effects
lubricant: an additive which facilitates processing or prevents sticking of a plastic formulation
masterbatch: a masterbatch is a concentrate of colorants or additives properly dispersed into a carrier polymer, which is then blended into the natural polymer to be coloured or modified
MFI: (melt flow index) the weight of polymer melt in grams forced through an orifice by a specified weight load in 10 min at a specified temperature.
migration: the transfer, usually undesirable, of a material from a plastic body to a contacting solid or liquid
monomer: a compound consisting of molecules each of which can provide one or more constitutional units
opacity: the property of an object to obstruct the penetration of light
pellet: a granule of a preformed moulding material having relatively uniform dimensions in a given lot, used as a feedstock in moulding and extrusion operations
pigment: substance consisting of particles that are practically insoluble in the application medium, used chiefly as a colouring material.
plastic: a material containing a high polymer as an essential ingredient and which at some stage in its processing into a finished product can be shaped by flow
plasticiser: a substance of low or negligible volatility incorporated in a plastic to lower its softening range and to increase its workability, flexibility or extensibility
plate out: the undesirable deposition of additives or pigments on machinery during processing of plastics.
polymer: a substance composed of molecules characterised by the multiple repetition of one or more species of constitutional units (monomers) linked with each other in such amounts that provide a set of properties that do not vary markedly with the addition or rem
polyolefins: the class of polymers made by polymerising relatively simple olefins
polypropylene: a tough, lightweight, rigid plastic made by the polymerisation of propylene gas
premix: an admixture of resin and additives in powder form, usually prepared by the processor shortly before use
reducer: a liquid system whose sole function is to reduce solids concentration, viscosity and colour strength of an ink or paint system
resin: any polymer which may be incorporated in a plastic material, ink or paint system
rigidity: the property of materials to withstand failure in extensional, impact or flexural stress
slip additive: a substance which tends to make surfaces slippery i.e. reduce the coefficient of friction.
solvent: the liquid carrier of an ink or paint systems where resins and additives are dissolved and/or suspended
solvent retention: incomplete evaporation of the volatile fraction of an ink or paint system during application
stabiliser: a substance used in the formulation of plastics to assist in maintaining the properties of the material at or near their initial values during processing and service life
suspension: a dispersion of a solid into a liquid
titanium dioxide: a white pigment available in two crystalline forms, rutile and anatase, the former being the most widely used white and opacifying pigment in thermoplastics, printing inks and paints.
UV absorber: an additive which protects materials by absorbing UV radiation.
UV stabiliser: additive which stabilises organic materials against UV radiation.
varnish: a liquid system whose sole function is to reduce pigment concentration in an ink or paint system
warpage: dimensional distortion of a plastic object after moulding or other fabrication
weathering: the process of material ageing (usually degradation) due to direct outdoor exposure
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