P84 Fibre Technical Brochure
Transkript
P84 Fibre Technical Brochure
P84® Polyimide Fibres Properties, Technical Data and Product Range P84® Fibre Characteristics Chemical Structure The P84® fibre is a polyimide based fibre with a typical textile character. Polyimides are known to be used in a wide range of operating temperatures starting from cryogenic applications and ending with high temperature applications at the limits of polymer based materials. The thermal stability is based on the aromatic backbone of the polymer. The fibres do not melt. Despite their halogen free structure they exhibit a high LOI of 38 %, which means the P84 fibres are classified as non flammable. P84® fibres have a rather unique cross section offering the highest specific surface of all available standard textile fibres. Cross Section of P84® Fibres The unique multilobal cross section offers up to 90 % more surface area compared to conventional round fibres and is the key advantage of P84®. This increased surface area results in the highest filtration efficiency of conventional fibres, even for sub micron particles. The fibres meet the requirements of all common textile processing steps. Besides standard grades, micro denierfibres are part of the production range. 2 | P84® Fibre Characteristics Product Range P84® fibres are available as staple fibres and multifilament yarn. Staple Fibre Available Types: 0.6, 1.0, 1.7, 2.2, 3.3, 5.5 and 8.0 dtex Cut Lengths (Standards): 53, 60, 80 mm Special Cut Lengths: 2,5-120 mm Bales: 150 kg and 200 kg Colour: natural golden yellow or spundyed Filament Yarn Available Type: 1060 dtex, 480 single threads Twist: 80 t/m Packaging: 12 cones, 3,5 kg each Colour: natural golden yellow Spundyed Fibres & Filaments available on request Color: black, navy-blue, orange, brown olive, dark gold P84® Fibre Characteristics P84® Fibre Characteristics Units Units Tenacity (dry) 38 cN/tex 4,3 g/den Elongation 30 % Shrinkage (@240 °C, 15 min.) <3% Density 1.41 g/cm3 Limiting Oxygen Index (LOI) 38 % Glass Transition Temp. (Tg) 315 °C Moisture Gain at 20 °C (60 % rel. hum.) 3% Properties 88 lb/ft3 599 °F The shown values together with the shape of the tension/elongation curve (see diagram) demonstrate that P84® is a typical textile fibre. P84® Fibre Characteristics | 3 P84® Fibre Characteristics P84® Stress/ Elongation Behaviour Stress/Elongation Behaviour Elongation [%] Stress [cN/tex] 40 35 30 25 20 15 10 5 0 0 5 10 15 20 25 30 ▬ Fibre titer: 2,2 dtex As P84® fibres show a typical textile character the fibre can be processed on standard carding and needling equipment. According to the data, which show a low modulus and a relatively high elongation, P84® is very well suited for textile applications and can be processed using standard textile equipment. The irregular lobed cross section and the crimp are responsible for the bulkiness and the volume of the fibre. P84® Fibre Shrinkage Characteristics P84® Fibre Shrinkage Characteristics Temperature [°C] Shrinkage [%] 60 50 40 30 20 10 0 250 260 270 280 290 300 310 320 330 340 350 ▬ P84®; Test Duration: 30 min During the manufacturing process, the fibres are stretched and the polymer molecules are getting oriented to a certain extent. When exposing the fibres to temperatures near the glass transition temperatures, a reorientation of the molecules takes place and the fibres shrink. The diagram shows the significant increase of the shrinkage after 30 minutes exposure at 315 °C (599 °F) and beyond. 4 | P84® Fibre Characteristics Specific Surface Area Specific Surface of Different Fibre Materials as Function of the Fibre Fineness Fibre Titer [dtex] Surface Area [m /kg] 2 600 550 500 450 400 350 300 250 200 150 100 50 0 4 ▬ P84® ▬ Procon™/Trilobal 3 ▬ m-aramide 2 1 0 ▬ PPS The large surface area primarily depends on the cross section and the fibre titer (fineness). All other fibres with same titer do not meet the specific surface area values of P84®. P84® Fibre Moisture Gain at 20 °C P84® Fibre Moisture Gain at 20 °C Relative Humidity [%] Moisture Content [%] 5 4 3 2 1 0 0 10 20 30 40 50 60 70 80 ▬ P84®; 20 °C, 60 % relative Humidity At standard conditions of 20 °C (68 °F) and 60 % relative humidity, the moisture gain of P84® fibres is 3 %. P84® Fibre Characteristics | 5 P84® Fibre Characteristics Service Temperatures Max. Service Temperatures of Different Fibre Materials N PA °C , PE T S PPide m ra m -a P84 PTF E PAN, PET (125 °C, 257 °F) PPS (200 °C, 392 °F) m-aramide (210 °C, 410 °F) P84 (260 °C, 500 °F) PTFE (275 °C, 527 °F) The acceptable average temperature depends on the environment and can be significantly lower than the maximum service temperature. The aromatic backbone ensures temperature stability over a wide range of operating conditions. The peak temperature for the P84® fibre is limited to 260 °C. This is well below the glass transition temperature of 315 °C. Chemical decomposition starts beyond 450 °C without formation of reasonable amounts of harmful substances. The acceptable average temperature in the actual application is depending on the composition of the environment and the expected service life. Short Term Temperature Stability of P84® Short Term Temperature Stability of P84® Temperature [°C] Weight [%] 100 75 50 25 0 0 100 200 300 400 500 600 ▬ P84® *Medium: Air, Heating Rate: 20 °C/min When exposed to high temperatures, P84® degrades the same way as many other organic polymers, leaving a carbon structure. However, the decomposition temperature is extremely high, as shown in the diagram. 6 | P84® Fibre Characteristics P84® Fibre Isothermal Weight Loss P84® Fibre Isothermal Weight Loss Time [min] Weight [%] 100 300 °C / 350 °C 400 °C 75 450 °C 50 500 °C 25 0 600 °C 0 50 100 150 200 250 300 ▬ P84® The weight loss of P84® is recorded versus time at different temperatures. Up to a temperature of 350 °C (662 °F) the weight loss is below 3 % and corresponds to the moisture content of the fibre. Differential Scanning Calorimetry (DSC) Diagram of P84® in Air Differential Scanning Calorimetry (DSC) - Diagram of P84® in Air Temperature [°C] Endothermic Heat Flow [mW] 25 Loss of water Tg 20 Onset X = 349,945 °C Onset Y = 20,0779 mW 15 10 5 0 50 100 150 200 250 300 350 400 450 500 ▬ Fibre titre: 2,2 dtex ▬ Tg This diagram shows, whether a material consumes or generates thermal energy during a defined temperature program. Especially changes of the structure and melting temperatures can be detected by using this method. P84® has no peaks indicating crystalline regions or melting behaviour, only a glass transition temperature is observed. P84® Fibre Characteristics | 7 P84® Fibre Characteristics Thermal Conductivity Thermal Conductivity T[K] λ [W/(mK)] 0,004 0,0035 0,003 0,0025 0,002 0,0015 0,001 0,0005 0 0 50 100 150 200 250 300 350 400 450 ▬ P84®, random card fleece ▬ Polyester, PP The very low thermal conductivity of P84® fibres is used to design fleece constructions for insulating cryogenic processes. Electric Charge of P84® Fibres Electric Charge of P84® Fibres Length[mm] Charge Intensity [pC/m] 200 150 100 50 0 -50 25 30 35 40 45 50 ▬ before exposing ▬ after exposing The diagram schows the electric charge along the length of a P84® fibre before and after exposing to an electric field using a corona charge of 20 kV. All fibres do have either positive or negative charges due to functional groups of the polymer and electrostatic excess charges. 8 | P84® Fibre Characteristics Chemical Properties of P84® Chemical Properties of P84® Concentration [%] Temp. [°C/°F] Time [hrs.] Effect on tenacity Sulphuric acid 10 20/68 100 no Nitric acid 10 20/68 100 no Hydrochloric acid 20 50/122 24 minimal Hydrobromic acid 37 20/68 100 no Hydrofluoric acid 40 20/68 100 no Acetone 100 20/68 1000 no Benzene 100 20/68 1000 no Perchloroethylene 100 70/158 168 no Chemicals no = 0 to 15 % Loss in tenacity, minimal = 16 to 30 % Loss in tenacity P84® provides good chemical stability to all common solvents, such as alcohols, ketones, chlorinated hydrocarbons and a wide range of other chemicals. It also offers high resistance to fats, oil and fuel. In addition, P84® fibres have a proven record of good resistance in a broad range of the pH-scale. Oxidative Aging Loss of Tensile Strength of Needle Felts due to Oxidative Aging Time [days] Tensile Strength [%] 140 120 100 80 60 40 20 0 0 50 100 150 200 250 300 350 400 ▬ P84® ▬ m-aramide Fibres exposed to air at high temperatures are deteriorated by oxygen. The experimental results shown in the chart were carried out at 210 °C (410 °F) and show superior performance of P84® compared to m-aramides. P84® Fibre Characteristics | 9 P84® Fibre Characteristics Hydrolysis Stability Hydrolysis Stability of Filter Fabrics @ 50 vol% Moisture, 170 °C Duration [days] Tensile Strength [N] 1000 900 800 700 600 500 400 300 200 100 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 ▬ P84® ▬ m-aramide ▬ PPS Even under extremely high moisture contents, P84® outperforms many of its competitors, being available for high temperature filtration applications. Limiting Oxygen Index (LOI) of Fibres Limiting Oxygen Index (LOI) of Fibres O2 [%] PTFE 95 PPS 40 P84® 38 m-aramide 28 PET 22 PA 22 0 20 40 60 80 100 ▬ PTFE ▬ PPS ▬ P84® ▬ m-aramide ▬ PET ▬ PA; according to ASTM D7438-08e1 The LOI indicates the level of oxygen needed to keep the material burning after ignition. P84® is classified as non flammable in atmospheric conditions. 10 | P84® Fibre Characteristics Emission of Toxic Gases during Degradation Emission of Toxic Gases during the Degradation of Fibres m-aramide wool p-aramide PAN P84® Emission [ppm] 125 123 100 93 82 75 73 50 25 0 NOx HCN 28 25 15 15 4 NOx HCN NOx HCN NOx HCN NOx HCN ▬ m-aramide ▬ wool ▬ p-aramide ▬ PAN ▬ P84® Source: "Toxic Products from Burning Textiles". Shirley Institute Manchester Gas volume and gas composition are strongly depending on conditions like excess or shortage of oxygen. Under the chosen conditions, P84® fibres show the lowest generation of toxic HCN (cyanic acid). Toxic Emissions Toxic Emissions acc. to ATS 1000.001 or BSS 7239 Emission [ppm] Chemicals 3500 CO 1 500 HCI 0 200 HF 0 100 SO2 0 100 NO2 3 150 HCN 1 0 100 200 300 400 500 ▬ Emission limit ▬ P84® fibre According to ATS 1000.001 which limits the toxic emissions for aircraft interior, P84® shows excellent performance. P84® Fibre Characteristics | 11 Legal References This information and all further technical advice is based on our present knowledge and experience. However, it implies no liability or other legal responsibility on our part, including with regard to existing third party intellectual property rights, especially patent rights. In particular, no warranty, whether express or implied, or guarantee of product properties in the legal sense is intended or implied. We reserve the right to make any changes according to technological progress or further developments. The customer is not released from the obligation to conduct careful inspection and testing of incoming goods. Performance of the product described herein should be verified by testing, which should be carried out only by qualitfied experts in the sole responsibility of a customer. Reference to trade names used by other companies is neither a recommendation, nor does it imply that similar products could not be used. P84 is a registered trademark of Evonik Industries AG or one of its subsidiaries. Procon™ is the trademark of Toyobo Co., Ltd. Evonik Fibres GmbH Gewerbepark 4 4861 Schörfling Austria phone +43 7672 701-2891 fax +43 7672 968622 www.P84.com