ABS

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ABS an Engineering Plastic

Description & TypesProperties & GradesApplication & UsesProcessing

Description & Types

ABS resins are thermoplastic resins composed of three different monomers I.e, ACRYLONITRILE, BUTADIENE AND STYRENEACRYLONITRILE stands- Tensile, Strength, Hardness, Heat resistance, Chemical Resistance etcBUTADIENE improves- Impact StrengthSTYRENE improves Processability

ABS has an combination of Mechanical, Thermal & Chemical Resistance. I.e (Tough; Hard & Rigid Material).

Acrylonitrile butadiene styrene

Acrylonitrile

Chemical ResistanceFatique ResistanceHardness & RigidityMelt Strength

H2C=CH

C=N

Butadiene

Low Temprature DuctilityImpact resistanceMelt Strength

H

C R

HC C

Styrene

Heat ResistanceProcessabilityColoringHardness & RigidityHC = CH2

Properties

ABS is derived from acrylonitrile, butadiene, and styrene. Acrylonitrile is a synthetic monomer produced from propylene and ammonia;Butadiene is a petroleum hydrocarbon obtained from the C4 fraction of steam cracking;Styrene monomer is made by dehydrogenation of ethyl benzene - a hydrocarbon obtained in the reaction of ethylene and benzene. The advantage of ABS is that this material combines the strength and rigidity of the acrylonitrile and styrene polymers with the toughness of the polybutadiene rubber.The most important mechanical properties of ABS are impact resistance and toughness.A variety of modifications can be made to improve impact resistance, toughness, and heat resistance.

These electron micrographs give an idea of what ABS plastic looks like on the surface.

The three pictures look totally different, yet they are all ABS polymer.If you were to zoom in even further, the polymer lattice of the acrylonitrile / styrene/ butadiene terpolymer would look something like this:

It is this cross-linked lattice that gives the plastic the required strength, as styrene is a brittle material;However, the styrene partly fills in the holes within this lattice work as well as cross-linking to the acrylonitrile.The butadiene has a similar effect, as well as dispersing in the molten polymers.ABS was one of the first commercial plastics and was developed in 1948.As engineering plastics go, its not that sophisticated and has been superceded by far superior polymers, but they are a lot more expensive, hence manufacturers tend to stick to ABS on cost grounds.

Properties of ABS

Excellent freedom of DesignSuperior Dimensional Stability, Rigidity & ToughnessGood surface glossExcellent Chemical, Resistance & Non Corrosive Better Surface Hardness Better Insulating PropertyLight WeightGood Low Temperature Impact StrengthAvailability of built in good attractive coloursOdourless, TastelessPossible to imply in all Techniques e.g spraying; Screen Printing; Metallizing, Eletroplating without any surface treament.

Grades of ABS

Graded by Injection Moulding; Extrusion & Thermoforming.Moulding can be graded asGeneral pupose;High Impact;High Gloss;High Flow;Heat Resistant;ElectroplatingExtrusion can be graded asLuggage;Refregerator lines;COP Sleeves.Alloys of ABS PC AlloyPVC Alloy

Plastic extrusion molding

Plastic extrusion molding is a process of producing a continuous work piece by forcing molten plastic through a shaped die.As the hot material exits the die the material is carried along a conveyor, cooled, and cut to the desired length.In plastic extrusion molding thermoplastic materials are fed from a hopper into the heated barrel of an extruder.A rotating helical screw inside the barrel pushes the plastic through the barrel toward the die located at the end of the machine.A key advantage of plastic extrusion molding is it's low cost.

Shapes compatible with extrusion molding are those having a constant cross-section.A few examples of parts often made by plastic extrusion molding include window molding, electronic enclosures, door insulation seals, pipes, rods, etc.The process requires a custom steel die in the shape of the part cross section.Cost reduction options including reducing cross section area, reducing wall thickness and selection of low cost material.

Plastic Extrusion Molding Design Considerations

Walls must not be too thick to provide cooling.Use rounded corners.Use uniform wall thickness. Long items will have a slight curvature. Ends are rough cut.

Machines of Plastics Extrusion Molding

Plastic extrusion molding of ABS

ABS Molding or Extrusion Compound

Product Description EXTRUSION IS A VERY IMPORTANT METHOD TO MAKE PLASTIC PRODUCTS

Low Gloss ABS

Low Gloss Materials are used for Automobiles Part

Ultra Super Heat Resistant ABS

Very High Heat Resistant

Medium Resistant Impact ABS

THIS IS THE GERERAL PURPOSE ABS

High Impact ABS

This is Strong Plastic ABS

Heat Resistant ABS

THE MATERIAL SHOULD WORK IN HIGH Temperature, FOR INSTANCE, AUTOMOBILE OR HAIR DRYER SHELLS

Plating ABS

IT IS VERY IMPORTANT TO ABS USING, BUT NOT ALL ABS GRADE SUITABLE FOR PLATING

Glass Fiber Reinforce

WITH GLASS FIBER REINFORCE WORK, THE RIGIDITY OF ABS IS LARGELY IMPROVED

Flame Retardant ABS

Injection Molding

Injection Molding

Plastic Injection Moulding with ABS Plastics

Different grades of ABS plasic available today including high-impact, glass-filled, transparent and high luster formulations, available in a wide range of colors for applications that include office machines, electronics and consumer related products.

Properties of ABS Plastic (Injection Moulding)

ABS is an amorphous thermoplastic copolymer blended from Acrylonitrile, Butadiene and Styrene.Being an amorphous thermoplastic, it is easily plastic injection molded, and it provides uniform shrinkage in both the flow and transverse-to-flow directions.This uniformity in shrinkage can be maintained over a wide processing range so precise dimensional control is easier to achieve when compared to a crystalline thermoplastic.Uniformity in shrinkage also results in minimal warpage after plastic injection molding.

ABS Thermaplastics Injection Molding

ABS, also known as acrylonitrile-butadiene-styrene, is a common engineering thermoplastic that has good impact strength and toughness along with mechanical and electrical properties that make it idea for a variety of uses:Medical devicesElectrical and electronicsHardwareEnclosuresBusiness machine and computer housingsIndustrial partsAppliances; Automotive & More

Factors Affecting the Injection Molding of ABS

A constant problem in injection molding processes is that of flash. Flash results in wasted material, time, money and poor product quality. The variables affecting the IM of ABS are:Injection pressure (35% or 45% of Maximum Pressure 62 Bars)Holding Pressure (35% or 45% of Maximum Pressure 62 Bars)Holding Pressure time (1 second or 4 seconds) affect the flash of ABS tensile specimens,The combination of variables that produced the least amount of flash are injection pressure (35%), low holding pressure (35%), and either low or high holding pressure time (1 or 4 seconds).

ABS molded products include:

Standard injection moldingThin- and thick-walled partsStructural foam molding

ABS properties:

Tough, versatile, cost-effective engineering thermoplasticGood impact strength Good rigidityGood surface appearanceFDA and U.L. grades availableUltraviolet light sensitive; requires stabilizers for weatherability

Secondary Operations for ABS Plastics Parts

Other ABS plastic injection molded components are parts that require post molding operations such as:secondary machining operations;installation of metal inserts,ultrasonic insertion anddecorated moldings using hot stamping, pad printing, and laser marking processes.A unique characteristic of ABS is the ability to chrome plate the material, thus lending itself to applications such as decorative trim, automotive parts, medical devices and toys.

Physical and Mechanical Properties :-ABS is hard and tough even at temperatures as low as -40oC.It has a high resistance to temperature fluctuations but has very limited weathering resistance and the mechanical properties tend to degrade quickly in outdoor exposure.It has low water absorption.

PropertyAproximate Value ABS 1Tensile strength55 - 80 MN/m2 2Tensile Modulus2 - 3 GN/m2 3Elongation at Break10 - 50 % 4Flexural Strength

SPECIFIC GRAVITY

The ratio of the weight of the molded piece as compared to the weight of an equal volume of water ASTM D792 ABS 1.04-1.07

Specific gravity of major polymers

ABS (High Impact)1.01 - 1.04ABS(Medium Impact)1.04 - 1.07ABS High(Heat Resistant)1.05-1 .08ABS Self Extinguishing 1.15 - 1.21

Thermal, Electrical and Optical Properties

Thermal Properties:-ABS has good high temperature performance and the softening point is generally higher than standard PS.The heat deflection temperature can be increased by several methods to between 120 to 130oC. ABS can be used down to about -40oC.

Fire Behaviour

Most ABS variants are flammable and will burn freely (giving off typical styrene odours).The flame and fire properties of ABS can be improved by blending bromine compounds at 15 - 20 pts phr - an expensive solution that seriously compromises the toughness of the material.Another method is to create an ABS/PVC blend and to let the chlorine on the PVC act as a fire retardent.

Electrical Properties

ABS has relatively good electrical insulating properties and products are suitable for secondary insulating applications. Optical properties Natural ABS is milky-opaque but can be easily coloured in a wide variety of colours.Special glass clear versions are available.

Chemical Resistance Property

ABS is resistant to most acids and alkalis, hydrocarbons, oils and fats.It is not resistant to acetone, ether, ethyl benzene, ethyl chloride and ethylene chloride.

AdvantagesLimitationsGood stain resistancePoor weathering resistance.Good impact resistance even at low temperatures.Must be dried before processing.Good electrical insulator and the electrical properties are unchanged by changes in humidity.Ordinary grades burn easily and continues to burn once the flame is removed.Low water absorption.Poor heat resistance.Easily electroplated to give good finish.Poor transparency but can be mixed with PMMA to improve.Good scuff or abrasion resistance.Scratches easily.Tough and stiff.Attacked by strong adds and alkalis, chlorinated solvents and can suffer from stress cracking in the presence of some greases.Wide colour range possible (natural is ivory colour).

Applications of ABS

Domestics Food Mixers & Grinders;Washing Machine; Hair Dryers; Vaccum Cleaners;Doors & body lines, handles of Refrigerators;Luggage'sBusiness Xerox Machine; Typewriters, Computers; Telephones;Textile;Electroplated parts;Automobiles etc

Application- Material ABS

Material ABS - acrylonitrile butadiene styrene ABS is an amorphous thermoplastic blend.The recipe is 15-35% acrylnitrile, 5-30% butadiene and 40-60% styrene.Depending on the blend different properties can be achieved.Acrylnitrile contributes with thermal and chemical resistence,The rubberlike Butadiene gives ductility and impact strength.Styrene gives the glossy surface and makes the material easily machinable and less expensive.

Generally, ABS has good impact strength also at low temperatures. It has satisfactory stiffness and dimensional stability, glossy surface and is easy to machine. If UV-stabilizators are added, ABS is suitable for outdoor applications

Computer mouseVacuum jugKimBox suitcaseCeramic advanced wet shave razorHedge cutter handleHandle for high pressure cleanerShaver, rechargeableEnsemble chair (ABS blended with PA)

Application Lego Building Bricks

The LEGO building bricks illustrate the attractive properties of ABS plastic: impact strength and glossy surface.The dimensional stability of ABS contributes to the narrow tolerances required when joining the building bricks.The bricks are mass produced by injection moulding

Application Product Computer Mouse

Products Computer mouse Three-dimensional decoration of these mice is achieved by water transfer technology. As it can be seen, decoration with very complex patterns and with a variety of colours can be achieved.One of the commercial names for water transfer technology is cubic printing

Application of Vacuum Jug

This vacuum jug illustrates how chemical resistancy and strength can be achieved at boiling temperatures.The black top of the jug is made from POM plastic which hardly absorbs the taste or smell from tea or coffee.The colored plastic jug furthermore shows how shiny scratch resistant surfaces are obtained using ABS plastic

Application-Product Kim Box Suitcase

This suitcase illustrates how a glossy surface is obtained using ABS plastic shaped with vacuum forming.The interior is made from PUR foam cut into shape using waterjet cutting.The suitcase is only produced in a very limited number for the Danish Museum of Craft and Design (Kunstindustrimuseum).It is used for transporting a collection of designed products that introduce children and teenagers to good industial design.

Application Ceramic ABS

Products Ceramic advanced wet shave razor The ceramic blade in this razor stays sharp up to 40 times longer than conventional razor metal blades.The razor is made from ABS plastic shaped with the insert moulding technique.The sharp blade is made of yttria stabilised zirconia ceramic.The present version of the razor is a prototype

Application- Product Hedge Cutter

Products Hedge cutter This hedge cutter shows how many different plastic materials are used in a product to obtain different properties.The handle and the shielding plate are made from ABS plastic which ensures good impact strength.The motor housing, in PA plastic, has good heat resistance.The sheath shows that a very long narrow hollow geometry can be produced in HDPE plastic by conventional injection moulding.

Application-Handle for High Pressure Cleaner

This hollow handle is produced with air assisted injection moulding.Better quality and reduced cost are achived compared with the traditional solution: a handle assembled from two half shells using snap locks.This handle is part of a high pressure cleaner. The cleaner can rotate around the joint at the bottom of the handle.The material is a blend that combines the qualities of ABS and PA

Application-Product Shaver Rechargeable

This shaver shows how soft rubber-like plastic is integrated with hard plastic.It also illustrates that it is realistic to produce strong, thin, sharp cutting blades with a complex geometry.The green rubber-like parts are produced by multicolor injection molding using PP for a stiff basis and SEBS plastics for the rubber-like surface.The hard blue part of the cover is injection molded in ABS plastic.The blades are made by electroforming

Application-Product Ensemble Chair

This stable chair is made from Stapron N which is a blend of ABS and PA plastics.The blend gives good acoustic properties (a sound unlike plastic!), a soft consistency, chemical resistance (coffee, food, alcohol), and good moulding properties.Using air injection moulding, air cavities are integrated into the seat and the back of the chair to give the right elasticity.In this way a good sitting comfort is achieved

Moulding Condition of ABS

Moulding Temperature C 180-240Injection Pressure a KGS/Cm 800-1400Mould Temprerature C 55-60Pre Drying of ABS Type of Oven : Air Circulating TypeThickness of Granules in Tray : 2 18mm Pre-drying Time : 2-3 HrsPre-drying Temperature : 80-90

Processing

ABS is an amorphous material and softens over a range of temperatures rather than melting quickly as do the crystalline materials.The materials have a broad processing window and can be processed on most standard machinery.ABS is available in standard and easy-flow grades and the easy flow grades are very good for complex mouldings.Pre-drying is not always needed for injection moulding with a vented cylinder but if drying is needed then 4 hours at 80oC is generally sufficient.Signs of moisture are stripes, streaks or bubbles in the moulding and if any of these are seen then the material should be pre-dried.

Injection Moulding

Mould temperature is usually between 30 and 80oC and the higher the mould temperature the better the surface quality.Weld lines may also become less prominent with increasing mould temperature. Moulding is carried out with an injection pressure of 1000 to 1500 bar and using a follow-up pressure of relatively short length but in the region of 30 - 60% of the injection pressure.

Back pressure using a normal cylinder is 100 - 250 bar and should be kept high to avoid air scorching of the material, a vented cylinder uses 20 - 50 bar and if this is too high then the easy flow grades will ooze from the vent port. Screw speeds can be high but should be set to ensure complete plastification. Injection speeds can be high but it is best to start slowly and then to inject rapidly.

1CYCOLACAR ABS3501901.052CYCOLACBDT6500 ABS3501831.053CYCOLACDFAR ABS3601841.044CYCOLACDSK ABS3701951.055CYCOLACGDM6400 ABS1821.056CYCOLACGDT2510 ABS3251981.057CYCOLACGDT6400 ABS1821.058CYCOLACGHT3510 ABS3502061.059CYCOLACGHT4320 ABS2111.0510CYCOLACGHT4400 ABS3701971.0211CYCOLACGPM4700 ABS3401981.0412CYCOLACGPM5500 ABS3801971.0513CYCOLACGPM5500F ABS3801951.0514CYCOLACGPM550M ABS4001951.0515CYCOLACGPM5600 ABS3301781.0516CYCOLACGPM5600F ABS3301981.0517CYCOLACGPM6300 ABS3601951.0518CYCOLACGPM6300F ABS3801951.0519CYCOLACGPT3800 ABS2601851.0220CYCOLACGPT4600 ABS2601821.0221CYCOLACGPT4800 ABS3101861.0322CYCOLACGPT5500 ABS3701871.05

23CYCOLACGSM ABS3301921.0424CYCOLACKJBABS3301901.2225CYCOLACKJTABS3401901.2026CYCOLACKJUABS3301901.2227CYCOLACKJWABS3301901.2328CYCOLACLABS2701881.0229CYCOLACLDMABS3401811.0430CYCOLACSEA2ABS3801621.1731CYCOLACTABS3401881.0432CYCOLACTEABS3401951.0433CYCOLACV100ABS4001621.2134CYCOLACVW300ABS3401681.2035CYCOLACX11ABS3101891.0436CYCOLACX15ABS3402051.0537CYCOLACX17ABS3802051.0538CYCOLACX37ABS3502301.0639CYCOLACZ48ABS3502171.0640CYCOLACZA2ABS3301921.0441CYCOLOYC1000HFABS+PC3602101.1242CYCOLOYC1110ABS+PC3402251.1443CYCOLOYC1110HFABS+PC3452301.1444CYCOLOYC1200ABS+PC3402351.1545CYCOLOYC1200HFABS+PC3402351.15

46CYCOLOYC1950ABS+PC3602101.1247CYCOLOYC2800ABS+PC3901761.1748CYCOLOYC2950ABS+PC3852031.1849CYCOLOYC2950HFABS+PC3752001.1850CYCOLOYLG8002ABS+PC3302201.1351CYCOLOYMC1300ABS+PC3002101.1052CYCOLOYMC8002ABS+PC3402301.1453CYCOLOYMC9000ABS+PC3452301.14

Extrusion

Screws should be chrome plated, single lead, full flighted constant pitch screws.Compression ratio should increase from around 2:1 to 2.5:1.In the absence of special ABS screws, low-compression PVC or shallow flighted PS screws can be used at low production rates. Reprocessing of up to 30% can be used provided the regrind has not been subjected to previous thermal degradation.

Material Grade Generic Flex. HDT(F) Spec name Mod. @264psi Grav. (X1000psi)1CYCOLACCGAABS2401921.032CYCOLACGPX2800ABS2401941.023CYCOLACGPX3700ABS3401981.044CYCOLACGPX3800ABS3001951.035CYCOLACGPX4500ABS4101961.056CYCOLACGSEABS3301921.047CYCOLACKLGABS3001901.248CYCOLACLDAABS2702001.029CYCOLACLSABS2601881.02

ABS

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