Contents Page1.0 Introduction 1

2.0 Preparation and Handling of PEEK-OPTIMA Polymer 22.1 Drying2.2 Re-work2.3 Thermal Stability and Break-down Procedures2.4 Inspection

3.0 Equipment and Processing 3

3.1 Pre-cleaning Injection Moulders and Extruders Equipment3.2 Shut-down3.3 Materials of Construction for PEEK-OPTIMA Polymer Processing Equipment

4.0 Injection Moulding 54.1 Machine Design

4.1.1 Barrel Temperatures4.1.2 Barrel Capacity4.1.3 Nozzles and Shut-off Systems4.1.4 Injection and Clamping Pressures4.1.5 Screw Design

4.2 Mould Design 74.2.1 Melt Flow4.2.2 Gating4.2.3 Shrinkage

4.3 Operating Conditions 94.3.1 Injection Pressures and Screw Speed

4.4 Troubleshooting 10

5.0 Extrusion 125.1 Machine Design

5.1.1 Barrel Temperatures5.1.2 Drive Motor5.1.3 Barrel Capacity and Residence Time5.1.4 Screw Design

6.0 Finishing Operations 136.1 Machining6.2 Annealing

6.2.1 An Overview of Annealing for Optimum Crystallinity6.2.2 An Overview of Annealing to Remove Stresses 6.2.3 An Overview of Annealing to Remove Thermal History and Shrinking

1.0 IntroductionPEEK-OPTIMA polymer is a high quality biomaterial suitable for medical implants. It has been manufactured to enhanced highstandards of production and rigorously tested and certified to key physical and chemical quality control parameters by Invibioand by an independent NAMAS/UKAS certified laboratory. The polymer is provided as granules for injection moulding andextrusion, and in rods for machining.

This document provides guidelines for the melt processing of Unfilled PEEK-OPTIMA polymer by injection moulding andextrusion and for the machining of rods.

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This document is NOT a guideline for filled, reinforced or other grades of PEEK-OPTIMA polymer, or forother Invibio producers. For processing information on other Invibio grades and materials, please contactInvibio Biomaterial Solutions at:

UK: Tel +44 (0) 1253 898000US: Tel +484 342 6004Asia Pacific: Tel +852 2366 4448info@invibio.com

2.0 Preparation and Handling of PEEK-OPTIMA PolymerPEEK-OPTIMA polymer granules are packed in a clean environment, free from extraneous contamination. It is imperative thatthey remain contamination free at all stages of preparation and subsequent handling during production. To aid this they arepresented in sealed, double bag-lined HDPE kegs fitted with a plastic tamper evident tab. DO NOT use if a keg of polymer hasa broken tab prior to opening. If the keg has been partly used (for example, from a previous moulding campaign) then it mustbe ensured that the polythene bag liners were sealed and that the lid was replaced at the earliest opportunity during theprevious session. Do not use the material if it has become contaminated by any means or if there is a chance that it has becomecontaminated. To avoid doubt, no material should be used if the processor cannot assure that the material has a ‘clean’ historyfrom delivery.

Double lining with polyethylene bags provides a means of minimizing the risk of contamination, as polymer can be removedfrom the kegs in clean, sealed bags for use in production.

PEEK-OPTIMA extruded stock shapes are also packed in a clean environment, free from extraneous contamination. To retaintheir original condition, the rods are supplied in a polymer sleeve, and should be kept in this condition during storage andhandling.

2.1 DryingWhilst PEEK-OPTIMA polymer is supplied nominally dry, it has been shown that the material typically absorbs up to 0.5% byweight of atmospheric moisture which can affect part quality. Consequently, it is strongly recommended that the granules arepre-dried to a level of less than 0.1% by weight prior to moulding. This can be achieved using an air-circulating oven at 150°C(300°F) for 3 hours or 160°C (320°F) for 2 hours or, nominally 12 hours at 120°C (250°F). Polymer should be spread onto cleantrays to a depth of no greater than 25mm (1 inch) to achieve the best results.

Extreme care should be taken to avoid any extraneous contamination from mixing with PEEK-OPTIMA polymer. It is imperative,therefore, that the material is dried in isolation from any other polymer materials or other potential contaminants. The ovenmust be clean and free from any agent of contamination. This could mean the use of air filtration in some air drying systems.

The use of hopper dryers is allowed if fitted with suitable clean air filtration.

2.2 Re-workDO NOT USE RECLAIMED MATERIAL

Re-work of ground material, such as sprues and runners, is not possible with PEEK-OPTIMA polymer because of the strong riskof contamination.

2.3 Thermal Stability and Break-down ProceduresIn common with other polymers, prolonged exposure to melt processing temperatures will result in some degree ofpolymer degradation; the severity of which will depend upon the duration. Under normal operation this will presentno problems, as PEEK-OPTIMA polymer is quite thermally stable. However, in the event of a protracted interruption tothe moulding cycle, care must be taken to avoid the formation and subsequent moulding of degraded material.

For interruptions of a short duration (less than 15 minutes) the degradation of PEEK-OPTIMA polymer is negligible and thebarrel temperatures may remain at the processing set point. However, as a precaution the barrel should be purged with freshPEEK-OPTIMA polymer prior to recommencing moulding. Mouldings should only be collected when inspection shows noevidence of discoloration or other indications of degraded material contamination. In the event of a prolonged shutdown(greater than 15 minutes), it is advisable to empty the screw of polymer and to reduce the temperatures as rapidly as naturalcooling will allow. The temperatures should be reduced to at least below 240°C (465°F) at which temperature PEEK-OPTIMApolymer will be solid and stable. Restart will require the temperatures to be re-adjusted to the processing temperature and thebarrel will need to be purged with fresh polymer.

If this material shows any evidence of degraded polymer that might have come from hang-up points in the screw/barrelassembly, it should be discarded. Only mouldings that are free from degraded material should be used. Persistent problemswith degraded material will require the screw and barrel assembly to be stripped and cleaned.

2.4 InspectionAll mouldings should be inspected for contamination. Contaminated mouldings should be discarded.

Partially degraded material is evident as brown or black streaks or speckles on a background of normal ‘buff‘ coloured

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PEEK-OPTIMA polymer. Mildly degraded material is darker than normal. Severely degraded material is brown or black.

Degraded material should not be confused with amorphous material, which is also dark brown, but which in contrast todegraded material reverts to the standard PEEK-OPTIMA polymer colour when annealed.

3.0 Equipment and ProcessingPEEK-OPTIMA polymer can be processed on conventional thermoplastic processing equipment with a high temperaturecapability. An appropriate size of machine should be chosen for the size of component to be moulded to avoid excessivepolymer residence time in the barrel.

The melting temperature of PEEK-OPTIMA polymer is approximately 340°C (645°F), but it is conventionally processed at 360°Cto 400°C (680°F to 750°F). At these temperatures the melt is stable and workable with a shear viscosity (for LT1) similar topolycarbonate melts. As with most conventional polymers there is a reduction of viscosity with increasing shear rate andtemperature. Figure 1 shows how PEEK-OPTIMA polymer compares with a range of conventional engineering polymers.

The viscosity has been shown to be shear rate and temperature sensitive. Polymer melt behavior can be classified by measuringviscosity over a range of shear stresses or shear rates at constant temperature. The viscosities of PEEK-OPTIMA polymer gradesLT1, LT2 and LT3 are plotted versus shear stress over two decades of shear rate in Figure 2.

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3.1 Pre-cleaning Injection Moulders and Extruders EquipmentIt is essential that PEEK-OPTIMA polymers and compounds are moulded or extruded on completely clean equipment. This willmean that the screw and barrel assembly should be stripped and cleaned beforehand. On no account should any othermaterial be used for purging the barrel, as this will present an unacceptable risk of contaminating the polymer. Only purgewith PEEK-OPTIMA polymer and use the same grade. Cleaning should avoid the use of solvents that might pose acontamination risk.

3.2 Shut-down Owing to the excellent adhesion between PEEK-OPTIMA polymer and the materials of construction, cooling the equipment tobelow the melting point with a fully charged barrel can lead to damage when the material shrinks as it cools. PEEK-OPTIMApolymer must be removed from the processing equipment before switching off the machine.

a) Empty the barrel of PEEK-OPTIMA polymer by turning the screw without feeding it with fresh polymer.

b) When the polymer stops flowing, terminate screw rotation and switch off the heaters.

3.3 Materials of Construction for PEEK-OPTIMA Polymer Processing EquipmentThe problem of machine wear is common to all engineering thermoplastics. To minimize wear in such processes, screws, diesand barrels should be hardened. The most common way of hardening tool steel is to nitride. This technique provides thesurface hardness necessary to resist excessive wear from the melt. Care must be taken to ensure that PEEK-OPTIMA polymerdoes not cool and solidify in contact with the nitride coating. The bond between the polymer and the nitride coating is oftensufficiently strong to lift the layer from the steel substrate.

The following steels are generally recommended for the construction of process equipment suitable for PEEK-OPTIMApolymers:

D2 Tool Steel (A martensitic chromium tool steel)

Stavax (A chrome alloy tool steel)

Hastalloy (A high nickel alloy)

Although not generally required, corrosion resistant and bi-metallic screws and barrels have proved satisfactory in service.Avoid copper and its alloys as some degradation may occur at PEEK-OPTIMA polymer processing temperatures.

The surface finish of metallic components which are used in melt transportation should be smooth and highly polished.Increasing the surface roughness of these components causes the melt to adhere locally to the metal, which increasesresidence time and disturbs polymer flow.

4.0 Injection MouldingMost standard reciprocating screw injection moulding machines are capable of moulding PEEK-OPTIMA polymer. Complex highperformance components can be readily mass-produced without the need for annealing or conventional machining.

4.1 Machine DesignPEEK-OPTIMA polymer and compounds can be readily injection moulded. However, due to the high melt temperature, certaindesign and process variables need to be considered. These are listed below.

4.1.1 Barrel TemperaturesIn order to successfully mould PEEK-OPTIMA polymer materials, the cylinder heaters connected to the barrel of the injectionmoulder must be able to reach 400°C (750°F). Most injection moulding machines are capable of these temperatures withoutthe need for modification. In the exceptional cases where modification is required it is a simple task to install highertemperature range controllers and ceramic heaters.

In order to achieve correct hopper feeding, the feed throat should be maintained between 70°C and 100°C (160°F and 210°F).Thermal conduction along the screw and barrel towards the hopper may reduce the feed efficiency. Thermal control in thefeed section may be achieved by water cooling, but care must be taken to maintain the rear zone temperature.

4.1.2 Barrel CapacityResidence times must be kept as short as possible due to the high processing temperatures of PEEK-OPTIMA polymer. Ideally,the barrel capacity should be between 2 and 5 times the total shot weight including sprue and runners. If it is necessary tomould PEEK-OPTIMA polymer on a machine which has a large number of shots in the barrel, then the rear zone temperaturesmay be reduced by 10°C to 20°C (18 to 36°F) below the recommended temperature settings.

4.1.3 Nozzles and Shut-Off SystemsThe nozzle of the barrel is in contact with the sprue-bush for a high percentage of the total cycle time during normaloperations. The temperature of the sprue-bush is considerably lower than that of the melt and the nozzle (see section 4.3).PEEK-OPTIMA polymer has a sharp melting point and will solidify quickly if the melt temperature is allowed to fall below 343°C(650°F). Therefore, it is important to ensure that an adequately large heater is fitted to the nozzle to prevent freeze-off and'cold slugging'. Extended nozzles are not generally recommended for use with PEEK-OPTIMA polymer because they increasethe likelihood of solidification in the nozzle.

Over the recommended process temperatures the viscosity of PEEK-OPTIMA polymer is generally still sufficiently high to allowan open nozzle system. Shut-off nozzles are not recommended because they frequently contain melt 'dead spots' and restrictinjection pressures. If excessive die drool is encountered, melt decompression should be employed in the process cycle.

4.1.4 Injection and Clamping PressuresThe injection pressures required for correct component moulding are system dependent. However, in general, injectionpressures rarely exceed 14 MPa (2000 psi) with secondary holding pressures of 10 MPa (1430 psi).

The projected area of the moulding and runner determines the clamp force required to prevent the mould opening undermaximum injection pressure. This typically corresponds to 50-80 MPa (500-800 bar, 7000 -11600 psi) for Unfilled PEEK-OPTIMApolymer. However, parts with thin sections and long flow lengths will require higher clamping pressures than those with thicksections and short flow lengths.

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4.1.5 Screw DesignMost general purpose and 'nylon' type screws are suitable for processing PEEK-OPTIMA polymer grades. Two such screws withappropriate length to diameter (L/D) ratios, are shown in Figure 3.

The minimum recommended L/D ratio screw is 16:1, L/D ratios between 18:1 and 24:1 are preferred. Long feed sections arerequired to prevent compaction of non-melted granules in the compression section of the screw. The compression ratio shouldbe between 2:1 and 3:1.

Check rings must always be fitted to the screw tip to ensure development of a full and sustained injection pressure. Ringclearance should allow for an unrestricted flow of material on forward movement of the screw. This typically corresponds toa 3mm (~1/8”) clearance from the screw tip diameter for a medium size moulding machine.

Figure 3: Screw Types Recommended for the Processing of PEEK-OPTIMA Polymer

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4.2 Mould DesignPEEK-OPTIMA polymer and compounds can be readily processed using many existing moulds. However, certain design criteriamust be met for successful moulding.

4.2.1 Melt FlowIt is recommended that sprues are at least 4 mm (1/6") thick and are as short as possible. Larger diameter sprues have beenshown to aid filling in complex moulds, which feature long flow lengths and thin sections. PEEK-OPTIMA polymer componentsrequire a minimum taper angle of 2° on the sprue and on the inside of the sprue bush for successful de-moulding. Whenpossible a 'cold-slug' well should be incorporated into the sprue design.PEEK-OPTIMA polymer moulds require circular or trapezoidal runners with large section thickness. Melt flow paths should bekept as short as possible and sharp changes of direction should be avoided. The success of moulding components with thinflow sections is a function of thermal, geometrical and pressure variables. An approximate guide to the effects of sectionthickness on the resultant flow length is shown in Figure 4.The data in Figure 4 were derived from measurements made on a spiral flow mould with an injection pressure of 140 MPa(140 bar, 20300 psi). It is not recommended to design moulds for Unfilled PEEK-OPTIMA polymer with a section thickness ofless than 1 mm (~40 mil).All materials in the PEEK-OPTIMA grade range are suitable for hot-runner mouldings. However, not all commercial hot-runnersystems are robust enough to be used with PEEK-OPTIMA polymer materials. A list of recommended systems may be obtainedfrom Invibio Ltd.

4.2.2 GatingThe size and style of gating appropriate for a moulding will depend on the melt volume, the number of cavities and thecomponent geometry required. Most gates are suitable for PEEK-OPTIMA polymer moulding although long thin flowsections are to be avoided. Gates should be as large as possible. The minimum recommended gate diameter or thickness is1 mm (40 mil) for Unfilled PEEK-OPTIMA polymer. Sprue gates should be between 1-1.5 times the thickness of the moulding.Submarine or tunnel gates should be avoided. Advice on suitable gates for moulding PEEK-OPTIMA polymer is available onrequest from Invibio.

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4.2.3 ShrinkageIn common with all injection moldable thermoplastics, PEEK-OPTIMA polymer components shrink while cooling in the mould.Shrinkage within mouldings is due to thermal contraction and the development of crystallinity.

PEEK-OPTIMA polymer is a semi-crystalline thermoplastics. Many of the outstanding physical properties which are associatedwith these materials are a function of the degree of crystallinity. The level of crystallinity may be controlled by melt and mouldtemperatures. Using the recommended injection molding conditions, PEEK-OPTIMA polymer mouldings should be nominally30% crystalline.

The mould shrinkage values shown in Table 1 are for fan-gated test plaques (150 x 150 x 3mm) (6" x 6" x 1/8") moulded underthe recommended conditions.

The difference between the 'with flow' and 'across flow' shrinkage values in Table 1 represents typical minima and maximaobserved in PEEK-OPTIMA polymer molding. The fan-gated plaque mold orientates the melt, fibers and crystalline regions, sothat a less orientated molding should exhibit mold shrinkage values between these two extremes. The annealed shrinkagevalues in Table 1 are obtained by post process thermal treatment in order to reach the maximum degree of crystallinity. Thesevalues of shrinkage may be expected in components which are subsequently used in high temperature environments.

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4.2.4 Shrinkage cont.Most injection moulding machines have the facility for a multi-stage injection. In order to reduce mould shrinkage and toenhance filling, a second stage packing pressure should be applied once the mould is full. The potential for severe mouldshrinkage may be prevented at the tool design stage by minimizing section thickness.

Moulded component tolerance may be defined as the dimensional variation observed in seemingly identical mouldings. Thetolerances shown in Table 2 were determined using the fangated test plaques previously described

(a) These data represent variation from the mean found in 20 samples.

4.3 Operating ConditionsThe optimum operating conditions for each individual injection moulding machine will depend on many variables. This sectionpresents an overview of the practical aspects of injection moulding PEEK-OPTIMA polymer based on our general experience.Table 3 shows the recommended temperatures required to successfully mould PEEK-OPTIMA polymer.

Invibio generally suggests that the mould surface is maintained between 175 and 205°C (350 and 400°F). These temperatureshave been found to give good mould filling characteristics and a high level of crystallinity within mouldings. Componentsformed with lower mould temperatures often have amorphous skin layers. These may be removed by post process annealing.However, it is advantageous to create uniform crystallinity throughout the specimen during moulding because post processcrystallization may lead to component distortion.

4.3.1 Injection Pressures and Screw Speed

Injection pressures of 7 to 14 MPa (1000-2000 psi) are initially used with holding pressures of 4 to 10 MPa (570-1430 psi).To create an homogeneous melt to aid consistency of shot size a nominal back pressure of 0.2 to 5MPa (30-715 psi) shouldbe used.

A screw speed of between 50 and 100 rpm is the optimum for transporting and melting PEEK-OPTIMA polymer. Screwspeeds lower than 50 rpm are to be avoided as this results in longer cycle times. Screw speeds higher than 100 rpm are notrecommended as they may result in excessive localised shear heating.

Table 3: Recommended Starting Temperatures for an Injection Moulding Machine Prepared for PEEK-OPTIMA Polymer

4.4 Troubleshooting

Table 4: Troubleshooting Guide

Fault Possible Cause Remedy

Short Mouldings Insufficient Material Injected Increase Injection PressureInadequate Flow of Melt Increase Barrel Temperatures

Increase Mould TemperaturesIncrease Injection Speed

Incorrect Design Increase Gates, Sprues or Runners SizeImprove Gates, Sprues or Runners SizeImprove Gates, Sprues or Runners DesignChange Position of GateIncrease Venting

Brittle Mouldings Overheating in the Barrel Decrease Barrel TemperaturesReduce Injection PressureIncrease Cycle Time

Moulded in Stresses Increase Barrel TemperaturesReduce Injection PressureIncrease Cycle TimeIncrease Mould TemperaturesIncrease Gates, Sprues or Runners Size

Weld Lines Increase Barrel TemperaturesIncrease Injection SpeedIncrease Mould TemperaturesChange Gate Design or Position

Cold Slug of Polymer Material Freezing in the Nozzle Increase Nozzle Temperaturein the Moulding Thermally Insulate Nozzle

Employ DecompressionUse a Sprue Break

Voids and Surface Sinking Insufficient Time or Pressure in the Mould Increase Injection PressureIncrease Holding TimeReduce Barrel Temperatures

Incorrect Mould Design Increase Gates, Sprues or Runners SizeIncrease Holding Pressure

Streaking Overheated Material Reduce Barrel TemperaturesReduce Nozzle TemperatureReduce Residence TimeReduce Injection SpeedReduce Screw Speed

Damp Material Dry MaterialDead Spots in Barrel Streamline Barrel and Nozzle

Clean Screw, Barrel and NozzleCheck for Damages, Pitting, etc.

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Fault Possible Cause Remedy

Burn Marks Air Trapped in Cavity Reduce Injection Pressure

Reduce Injection Speed

Improve Venting of Cavity

Change Gate Position, Size or Type

Flashing or Mould Inadequate Locking Force Reduce Injection Pressure

Opening Reduce Injection Speed

Reduce Cylinder Temperature

Reduce Mould Temperature

Reduce Speed Setting

Increase Locking Force

Incorrect Mating or Re-grind and Re-align

Bending of the Mould Install Heavy Backing Plates

Check for Foreign Matter Between the Plates

Warping or Distortion Temperature Difference in the Mould Adjust Temperature so That it is the Same onBoth Halves of the Mould

Lack of Section Symmetry Consider Re-design of Cavity, Runners & Gates

Use a Temperature Differential Between the

Two Halves of the Mould to Compensate

Use a Cooling Jig

Increase Cooling Time

Increase Cooling Time

Early Ejection Reduce Mould Temperatures

Add More Ejectors Pins

Insufficient Rigidity Change Design of Components(e.g. Add Ribs, etc)

Increase Section Thickness

Jetting Material Entering the Cavity Too Quickly Change Position and/or Type of Gate

Melt too Cold Increase Melt Temperature

Excessive Shrinkage Processing Conditions Reduce Tool Temperature

Increase Injection Pressure

Increase Holding Pressure

Gate too Small Increase Gate Size

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5.0 Extrusion

5.1 Machine DesignPEEK-OPTIMA polymer and compounds can be extruded using conventional process technology. There are specificrequirements, which are detailed below.

5.1.1 Barrel TemperaturesCylinder heaters must be capable of reaching 400°C (750°F) and maintaining set temperatures to within ±2°C. Therefore, castaluminum heaters are not suitable and should be replaced with either high temperature alloy or ceramic heaters. Cylinderheaters should cover all exposed metal surfaces to ensure an even temperature distribution. Areas that cannot be heateddirectly should be covered with high temperature thermal insulation to prevent the formation of 'cold spots'.

5.1.2 Drive MotorThe power output of the motor must be at least 0.25 HP/Kg/hr.

5.1.3 Barrel Capacity and Residence TimeThe size and the output of the extruder should be matched to obtain a short residence time, typically 5 to 10 minutes. Thereshould be no ‘dead spots’ i.e. gaps around flanges or badly fitting blanking plugs. All internal surfaces should be cleaned andpolished before extrusion commences.

5.1.4 Screw DesignThe materials in the PEEK-OPTIMA polymer grade range are compatible with most conventional screw designs. The only screwspecifically not recommended is a continuous compression ‘PVC’ type. This screw has virtually no feed section which results inthe compaction of granular polymer leading to excessive torque.

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6.0 Finishing Operations

6.1 Machining

The following table provides a guide to the tool geometry and materials required for machining PEEK-OPTIMApolymer. The process of machining and finishing polymeric materials is prone to propagating residual stresses andtherefore annealing of PEEK-OPTIMA parts is recommended to relieve stress (see section 6.2 Annealing). Whenlarge material volumes need to be machined it may be necessary to relieve residual stress after rough cutting ofthe part.

Due to the low thermal conductivity of polymeric materials, machining processes tend to generate heat rapidly andit may be necessary to use a coolant. For all grades of PEEK-OPTIMA water is generally recommended. However, it ismore preferred that parts are machined dry, which can be achieved by selecting cutting speeds and removal ratesthat generate minimum heat.

* If a coolant is used, it must be selected by the device manufacturer and must not affect the biocompatibility ofPEEK-OPTIMA polymer.

6.2 AnnealingComponents formed from PEEK-OPTIMA polymer materials may be annealed to increase levels of crystallinity, remove anythermal history, limit subsequent dimensional changes at high temperatures or to remove stresses. The appropriate annealingprotocol will depend on the objective of the process.

6.2.1 An Overview of Annealing for Optimum CrystallinityIncreasing crystallinity within a component may be necessary if a brown amorphous skin is observed (this can also be eliminated by increasing mould temperature) or enhanced strength and chemical resistance is required.

a) Dry the component for a minimum of three hours at 150°C (300°F).

b) Allow the component to heat up at 10°C (18-20°F) per hour until an equilibrium temperature of 200°C (390°F)is reached.

c) The holding time for components is dependent on section thickness. It is recommended that annealingtemperatures are held for at least 4 hours.

d) Allow the component to cool at 10°C (18-20°F) per hour until the system falls below 140°C (280°F).

e) Switch off the oven and allow the component to cool down to room temperature.

Annealing temperatures close to 300°C (570°F) have been used to maximize mechanical performance (strength and modulus) and chemical resistance. However, these effects may be accompanied by embrittlement and surface oxidationbecause of the high annealing temperature.

6.2.2 An Overview of Annealing to Remove StressesInjection moulding or machining operations may impart stress to a component. This stress reduces the physical performance of devices and may be reduced by annealing the sample.

a) Dry the component for a minimum of three hours at 150°C (300°F).

b) Allow the component to heat up at 10°C (18-20°F) per hour until an equilibrium temperature of 250°C (480°F)is reached.

c) The holding time for components is dependent on section thickness. It is recommended that annealingtemperatures are held for at least 4 hours.

d) Allow the component to cool at 10°C (18-20°F) per hour until the system falls below 140°C (280°F).

e) Switch off the oven and allow the component to cool down to room temperature.

6.2.3 An Overview of Annealing to Remove Thermal History and Shrinkage Dimensional stability over a wide temperature range may be crucial to some applications. Components may be annealedto remove distortion effects or thermal history.

a) Dry the component for a minimum of three hours at 150°C (300°F).

b) If the maximum in-service temperature (including sterilization) exceeds 150°C, allow the component to heat up at10°C(18-20°F) per hour until an equilibrium temperature is reached equal to this temperature.

c) The holding time for components is dependent on section thickness. It is generally recommended thattemperatures are maintained for at least 4 hours.

d) Allow the component to cool at 10°C (18-20°F) per hour until the system falls below 140°C (280°F).

e) Switch off the oven and allow the component to cool down to room temperature.

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DisclaimerThe information contained herein is believed to be an accurate description of the typical characteristics and/or uses of Invibio product(s). However, it is yourultimate responsibility to determine the performance, efficacy and safety of using Invibio product(s) for a specific application. Suggestions of uses should notbe taken as inducements to infringe any particular patent or as a representation that the product is suitable for such uses. Invibio makes no warranties,express or implied, including without limitation, a warranty of fitness for a particular purpose or of intellectual property non-infringement, including, but notlimited to patent non-infringement, which are expressly disclaimed, whether express of implied, in fact or by law. Further, Invibio makes no warranty to yourcustomers or agents, and has not authorized anyone to make any representation or warranty other than as provided above.

Invibio shall in no event be liable for any general, indirect, special, consequential, punitive, incidental or similar damages, including without limitation,damages for harm to business, lost profits or lost savings, even if Invibio has been advised of the possibility of such damages, regardless to the form of action.

Invibio and PEEK-OPTIMA are registered trademarks of Invibio Ltd in the United States, European Community and elsewhere. Biomaterial Solutions is atrademark of Invibio Ltd.

Invibio Ltd.Technology Centre, Hillhouse InternationalThornton Cleveleys, LancashireFY5 4QDUnited KingdomTel: +44 (0) 1253 898000FAX: +44 (0) 1253 898001

Invibio Inc.300 Conshohocken State RoadWest Conshohocken, PA 19428USA 866-INVIBIO (468 4246)Tel: +484 342 6004FAX: +484 342 6005

Invibio Ltd.Metropolis TowerUnit 1202-3, 12th Floor10 Metropolis DriveHunghom, Kowloon, Hong KongTel: +852 2366 4448 FAX: +852 2366 7667

info@invibio.com www.invibio.com

PO-ENG-B-02(07/09.02)