Evolving Injection Moulded Polypropylene Products for Industrial Sectors

Transcription

1 Evolving Injection Moulded Polypropylene Products for Industrial Sectors Dr. Rajeev Basargekar Polymer Research & Technology Centre, Reliance Industries Ltd. 1

2 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

3 Prologue India on the march Growth in Industrial and service sectors Growth in consumers and risers Diverse sectors have to work with synergy Petrochemical, engineering industry, Machine tool industry & Design service industry to work together to play with materials & energy. Engineering industry (Automobiles, Appliances, Teletronics ), Injection moulding & Polypropylene are getting closely bonded together. An attempt to have a glance at the bond. Sept 27, 2007 IPI Windsor Endowment Lecture

4 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

5 Evolved products on Horizon All technology products used in day-to-day life by engineering industry are using plastics Automobiles are seen covered by plastics and synthetic fibres from inside & outside. Appliance-bodies as well as interior parts are from plastics. Energy efficient production & conversion leading the change Injection moulding leading the processes to make plastics parts which are assembled by engineering industry. Polypropylene leading the plastics materials used by the engineering industry. Sept 27, 2007 IPI Windsor Endowment Lecture

6 Evolved products on Horizon World s first integrated fender module with PP based paintable skin panel for the fender introduced in the X5 model of BMW. Supplied by Plastic Omnium. Number of parts are integrated in the fender module. Skin panel, carrier, head-lamps, sidelights, fog-lamps, wiper-washer tank Skin panel injection moulded PP compound from Borealis, carrier injection moulded from 30 % PP-LGF. A class finish, paintability, low CLTE, stiffness & toughness. 50 % weight reduction achieved. Sept 27, 2007 IPI Windsor Endowment Lecture

7 Evolved products on Horizon SPE 2006 automotive innovation awards: Body interior award: For in-line compounding/injection moulding of 2 piece vibration welded IP structural duct assembly: PP compound from Basell, part producer Intertec systems, used in 2007 MY Daimler Chrysler Dodge Nitro 15% cost saving (Vs PC/ABS Chassis / Hardware award: For integrated, cable driven rail-less window regulator system for door modules. Glass filled PP (St. Gobain / Exxon), system producer Faurecia Interior systems used in in 2007 MY Daimler Chrysler Dodge Nitro Saving of 25 % weight & US $ 7 / vehicle. Sept 27, 2007 IPI Windsor Endowment Lecture

8 Evolved products on Horizon Daimler Chrysler smart car was introduced with PC-PBT body panels. Interview of Mr. Claus Maureder (Application Marketing Manager, Borealis) in Polymotive July/Aug 2007 issue reveals that: Overall plastics external skin for Smart for two will be using 26 Kg of PP per automobile. Tailgate flap of Renault Modus with class A surface & small gap dimensions, prepared on the basis of PP. All applications by injection moulding of PP based materials. Sept 27, 2007 IPI Windsor Endowment Lecture

9 Evolved products on Horizon Parts of Citroen made in PP compounds supplied by Sabic (Former DSM) Front bumper (with integrated fender) and lower grill moulded in paintable PP compounds. Supplied by Plastic Omnium Rear bumper in paintable PP compound supplied by Cadence Innovation, also available in UV stabilized unpainted. Door Panels in scratch resistant, stiff, tough PP compound with good flow, supplied by Faurecia. Sept 27, 2007 IPI Windsor Endowment Lecture

10 Evolved products on Horizon UP, 1, 1% POM, 2, 1% Other, 4, 3% Unidentified, 6, 4% PBT+PET, 14, 9% PP, 64, 43% PVC, 3, 2% PC, 3, 2% ABS, 4, 3% PE, 8, 5% PA, 20, 14% PUR, 19, 13% New Opel Corsa in Europe: Weight : 1293 Kg Plastics (with elastomers): 149 Kg 12 % w/w Polypropylene (Engineered): 64 Kg 44 % of Plastics Polymotive Jul/Aug 07 Glass, 33, 3% Elastomers, 57, 4% Aluminium, 114, 9% Cast iron, 124, 10% Plastics, 149, 12% Other & fluids, 94, 7% Steel, 722, 55% Sept 27, 2007 IPI Windsor Endowment Lecture

11 Evolved products on Horizon Polypropylene is a preferred material by automobile and appliance industries major sections of engineering industries. Majority of the products are from engineered polypropylene though 2 wheeler automobiles & appliances use direct grades with masterbatches. Majority of the products are prepared by injection moulding the only process which defines the x-y-z dimensions as desired consistently. Innovations are triggered by developments: In PP grades & engineered PP grades, In designs In injection moulding techniques/ processes. Sept 27, 2007 IPI Windsor Endowment Lecture

12 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

13 PP Usage in world PP in world : 43 % material processes by Injection moulding Global consumption of PP in various processes in 2006 & projected 2011 (Thousands of Tons) Total Homopolymer Random copolymer Impact Copolymer TPO-Elastomer Process Blow Moulding Fibres 11, Film & Extrusion coating Injection Moulding Sheet Other Total PP in injection moulding : > 30 % used in Appliances & Automobiles Global consumption of PP in Injection Moulding in 2006 & projected 2011 (Thousand of Tons) Homopolymer Random copolymer Impact Copolymer TPO-Elastomer Total Market Appliance Automotive Consumer / Houseware Packaging Other Injection Moulding Total Townsend report on PP Sept 27, 2007 IPI Windsor Endowment Lecture

14 PP-Usage in Asia/Pacific & India Asia/Pacific Consumption of PP in Injection Moulding 2006 & projected 2011 (Thousand Tons) Total Homopolymer Random copolymer Impact Copolymer TPO-Elastomer Market Appliance Automotive Consumer / Houseware Packaging Other Injection Moulding Total PP In Indian Injection Moulding & 2011 Prj (Thou ton) India Asia /Pacific Market Appliance Automotive Consumer / Houseware Packaging Other Injection Moulding Total (Asia Pacific figures do not include China & Japan) Townsend report on PP Sept 27, 2007 IPI Windsor Endowment Lecture

15 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

16 Expectations of Industrial sectors Industries as assembly units, passing on responsibilities of subassemblies to suppliers. Expectations that moulders should upgrade themselves to part / sub-assembly suppliers. Global sourcing followed. MNCs going in for localization only if part localization business cases are competitive to imports of parts. Stringent expectations of quality & quality systems: Elaborate supplier approval processes Emphasis on following quality systems QS9000 etc. Stringent Part approval processes: PPAP consisting of approval by Engineering, as well as approval by SQA for run@rate, transport packaging norms etc. JIT (Just in time) delivery preferred, location of suppliers preferred in the vicinity. Sept 27, 2007 IPI Windsor Endowment Lecture

17 Expectations of Industrial sectors Emphasis of engineering assembly units on: Assembly line should not stop. Legal requirements should be met: Example Bumper mounting durability Head impact testing for instrument panel Regulation for Outside Rear View mirrors There should not be any safety issues. There should not be walk-home failures/ failures in running. Fit & function should be satisfactory. No build problems & no field problems. Corresponding to each point processes are laid down. Sept 27, 2007 IPI Windsor Endowment Lecture

18 Expectations of Industrial sectors Automotive and appliance industries give primary importance to: Test- Specifications to be complied by parts Testing of assembly (if any) related to cycling of functionality & durability, functionality after exposing to defined adverse conditions. Functionality without rattles and squeaks. Durability after running of whole assembly under defined conditions: Durability run of automobiles on test tracks Durability of all parts after running a washing machine for defined cycles. Durability of refrigerators after keeping in different environments for specified time. Materials specifications are either provided or asked to be proposed so that part & assembly requirements are met. Sept 27, 2007 IPI Windsor Endowment Lecture

19 Expectations of Industrial sectors Typical requirements for auto interior parts: Dimensional accuracy KPCs related to assembly. Colour fastness to artificial light WOM Blue/Grey scale Resistance to cleaning agent Volatility of organic constituents (especially PVC) Resistance to synthetic perspiration Resistance to scratching (Especially for PP based parts) Resistance to temperature cycling no cracking, crazing, appreciable colour change and dimensional compliance. Resistance to odour Flammability (internal & legal requirement e.g. MVSS302) Falling weight impact at 30 deg C. Oxidation stability (168 hrs / 150 deg PP) Ref: GM spec GMI00004 Sept 27, 2007 IPI Windsor Endowment Lecture

20 Expectations of Industrial sectors Typical requirements for auto interior parts: Dimensional accuracy KPCs related to assembly. For unpainted self coloured - Exterior weatherability Xenon Arc WOM as specified. Resistance to humidity. Resistance to Heat ageing. Resistance to temperature cycling No cracking, crazing, discoloration & post cycling dimensional conformance. Resistance to SO2 & sulfide staining. Resistance to fuel, resistance to cleaning agents. Resistance to stone impact Falling weight impact strength. Painted components will require paint adhesion test after curing & after 72 hrs heat/humidity ageing apart from testing of paints. Ref: GM spec GMI00002 Sept 27, 2007 IPI Windsor Endowment Lecture

21 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

22 Polypropylene usage science Part requirements when translated to material specifications, Engineered PP production needed. In international scenario many resin manufacturers provide Engineered PP, in India these are provided by compounders. Compounding of PP involves: Use of appropriate grade for surface & mechanicals. Use of fillers (Talc, glass etc.) Use of impact modifiers Use of colourants Use of UV stabilizers Use of flame retardants Use of adhesion promoters (if necessary for paintable parts) PP painting involves cleaning by IPA, application of primer (made conductive by C black if needed), application of paint & curing of paint. Sept 27, 2007 IPI Windsor Endowment Lecture

23 Polypropylene usage science Modification of PP leads to change in behaviour of material in injection moulding. Understanding of basics of PP for injection moulding is useful for moulding of modified PP also. Characteristics relevant for injection moulding of PP: Rheological flow behaviour spiral flow. Thermodynamic specific heat & heat of fusion. Volumetric Shrinkage characteristics Morphological For shrinkage, warpage etc. Sept 27, 2007 IPI Windsor Endowment Lecture

24 Polypropylene usage science Rheological considerations: PP melts are pseudoplastic, viscosity less at processing shear rates of 10,000 to 40,000 s-1. Pseudoplasticity retained with filling with rise in viscosity. High MFI required for easy flow, yet spiral flow better indicator than MFI as spiral flow determined at realistic shear rates. Mould-flow analysis helps to ensure balanced filling. Spiral flow (CMS) MFI - Spiral flow Relationship MFI (g/10 min) Sept 27, 2007 IPI Windsor Endowment Lecture

25 Polypropylene usage science Thermodynamics: Heat in PP Melt Tg of PS Tm of PP PP Semi-crystalline materials have latent heat of fusion. Heat content in PP melts is higher than melts of PS, HIPS, ABS etc. Heat in PS Melt Heat Latent Heat PS The Sp heat of PP is also higher than PS/HIPS/ABS. The heat to be Furnished & removed is higher in PP Specific Heat Values: ABS 0.35 Cal. /g/deg C PS 0.32 PP 0.46 Latent Heat values: Temperature Range of melting. Temperature ABS and HIPS No latent heat Repol/Koylene PP HP: 90 J/g 21.5 cal./g Repol PP RCP: 60 J/g 14.4 cal./ Repol/Koylene PP ICP: 75 J/g 18 cal./g Sept 27, 2007 IPI Windsor Endowment Lecture

26 Polypropylene usage science Volumetric : At room temperature PP is semicrystalline. Consist of amorphous regions with low density, and crystalline regions with high density (> 1) Difference between melt density and solid density higher in PP than in case of PS/HIPS/ABS. Mould shrinkage data gives a useful indication and tool. Shrinkage depends on homopolymer content & crystallinity. (nucleation) Tg Temperature Tm Tg PP PS Typical ASTM Linear Shrinkages for PP (Get reduced by filling) PP Homopolymers: 1.2 to 1.45 &, PP-ICP:1.05 to 1.3 %, PP-RCP: % Sept 27, 2007 IPI Windsor Endowment Lecture

27 Polypropylene usage science Morphological Morphology of a moulded part is a result of flow during filling and subsequent solidification. Orientation ( & subsequent relaxation) of chains in melt with the imposed flow-field. Heat transfer between hot melt and cold mould. Crystallization kinetics under flow field. Shear Rate max at walls Shear induces orientation & can enhance rate of crystallization Cooling rate maximum at walls PP attains a skin and core morphology during injection moulding. At the skin there are oriented crystalline regions, at the core spherulites Sept 27, 2007 IPI Windsor Endowment Lecture

28 Polypropylene usage science Morphological Skin layer thickness contributes to tensile and flexural modulus, yet leads to anisotropy of properties. Non-uniform skin layer thickness lead to uneven shrinkage & warpage. Generally the skin layer thickness decreases with: Increasing melt temperature Increasing the distance from the gate in the flow direction. Decreasing resin molecular weight ( increasing MFI). Decreasing resin polydispersity (less with narrow MWD) Increasing injection speed. Increasing mold temperature. Incorporation of ethylene in polymer structure (random copolymers) Skin layer thickness increases with incorporation of fillers. Change in skin layer thickness in direction of flow leads to more shrinkage in flow direction and less in direction transverse to the flow For PP-ICPs, additional feature is dispersed phase morphology. Fine dispersion with spherical shape, not deforming during flow desirable. Sept 27, 2007 IPI Windsor Endowment Lecture

29 Polypropylene usage science Processing parameters affect crystallization, orientation & shear induced crystallization, hence affect properties. +1 perfect positive, -1 perfect negative & 0 no correlation. Ref : Injection Moulding Materials A. Whelan, Applied Sc. Pub. Sept 27, 2007 IPI Windsor Endowment Lecture

30 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

31 Availability of PP in India PP abundantly available in India. Manufactured by: RIL (Including IPCL) ~ 1.7 MMTA (~ 0.3 MMTA ICP) HPL ~ 0.26 MTA PP-ICPs mainly needed by Industrial sector: RIL produced PP-ICP in the MFI range 1.5 to 55 HPL produces in the MFI range 3 to 12. High MFI & High impact ICP, much needed by the sectors being introduced by RIL: MFI ~ 30, Impact Strength > 125 J/m and Flex. Mod. > 1000 MPa. Engineered PP i.e. PP-Compounds manufactured by Machino Polymers, Hydro S & S, Zylog, TIPCO, Aalekh, SJS Polyblends, PI Polymers, Premium Polyalloys, Xmold etc. Compounders use indigenous as well as imported PP. Sept 27, 2007 IPI Windsor Endowment Lecture

32 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

33 Use of Modified PP PP is modification friendly material: Can be modified by reinforcing and stiffening agents like glass, talc, platy clays etc to increase rigidity & strength. Can be modified by toughening agents like plastomers. Can be made flame retardant, UV resistant etc. Challenges for industrial products: Have higher strength/weight ratio Have low CLTE (Thermal expansion coefficient) Strength resembling glass-nylon / Metal Have high scratch resistance: Use of high isotacticity PP Have high gloss Sept 27, 2007 IPI Windsor Endowment Lecture

34 Use of Modified PP Several ways possible: Two new emerging ways Use of PP Nano-composites: Platy clays exploded (exfoliated) to increase L/T ratio substantially, compounded with PP with a compatibilizer / coupling agent to have higher strength/weight ratio. Use of less filler, less density & better strength. Material on the basis of imported exfoliated clay getting introduced in Indian market, researches to evolve materials on the basis of indigenous clay going on. Use of PP-LFT: Long glass fibre based PP produced. (upto 55 % Glass) Use of injection moulding machines with special screw designs to retain fibre length in product above 4 mm. (<0.5 mm if conventional glass filled PP used. Higher modulus, lower expansion, potential for metal replacement due to weight saving & cost saving through part consolidation. Sept 27, 2007 IPI Windsor Endowment Lecture

35 Use of Modified PP LFT PP being introduced in India by Indore Composites Product name PPLG30 PPLG40 PPSG30 PPSG40 Resin PP PP PP PP Test Method Units ASTM SI System Fiber type Glass Glass Glass Glass Fiber content (wt %) Specific Gravity Tesnile Strength ASTM D 638 Mpa Tensile Modulus ASTM D 638 Mpa Tensile Elongation (%) ASTM D 638 % Flexural Strength ASTM D 790 Mpa Flexural Modulus ASTM D 790 MPa Notched Izod Impact ASTM D 256 J/m Compressive Strength ASTM D 695 Mpa DTUL (o 1.82 Mpa) ASTM D C Skeletal Structure retained after Burning the resin. Sept 27, 2007 IPI Windsor Endowment Lecture

36 Use of Modified PP Products developed from 12 mm long LFT-PP Front-end module Bumper Beam Specially designed low compression screws Used to have fibre length in moulding at ~ 4 mm. Door-Panel Sept 27, 2007 IPI Windsor Endowment Lecture

37 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

38 Use of modified processes Various process modifications are possible & are getting developed with PP / Modified PP. Gas Assisted Injection Moulding (GAIM): Weight saving, Removal of sink-marks, warpage, added stiffness. Multi-material moulding : Advantages of synergy of properties. (Aesthetics & cost, Toughness with paintability & stiffness + strength) Sequential moulding Moulding with insert (molded or formed plastics / metal) Sandwich Moulding Sept 27, 2007 IPI Windsor Endowment Lecture

39 Use of modified processes Use of GAIM for automotive side mouldings to get part with no sink marks, no warpage, material saving. Side mouldings usually moulded from paintable / UV stabilized PP compound. Sept 27, 2007 IPI Windsor Endowment Lecture

40 Use of modified processes Use of multi-material moulding process can lead to reap the benefits of PP of low cost, low weight & recyclability. Modification friendliness of PP can be used to overcome shrinkage & adhesion issues with other materials. Modified PP with adhesion promoter and blowing agent can be used for core / inner layer & aesthetically acceptable / paintable PP compound or other materials like ASA can be used as external layer ICI/Austin Rover development achieved A class online PP wing for Maestro Van in form of sandwich of GF-PP core and toughened PP skin Thermoformed multilayer films can be placed in mould to mould a component. The colour, gloss and surface properties are provided by the film. Development by Mayco plastics with Daimler Chrysler describes use of such IMD for fascia made from TPO (PP compound) to pass all requirements. Sept 27, 2007 IPI Windsor Endowment Lecture

41 Use of modified processes Sept 27, 2007 IPI Windsor Endowment Lecture

42 Presentation Themes Prologue Evolved products on horizon Polypropylene usage scenario Expectations of Industrial Sectors Polypropylene usage science Availability of PP in India Use of modified Polypropylene Use of Modified Processes Epilogue Sept 27, 2007 IPI Windsor Endowment Lecture

43 Epilogue Design Styling, structural Benchmark studies Customer expectations Designing for assembly and dismantling Design analysis Innovation Materials Expected duty Spectrum of availability Existing & newly introduced Modifications Basic forms for further shaping Conversion Processes Spectrum of existing processes Special processes Process development Processes to suit materials Processes to suit assembly Sept 27, 2007 IPI Windsor Endowment Lecture

44 Epilogue Injection moulding of PP has evolved after that of styrenics & others as PP is comparatively young. Modification friendliness of PP has been exploited & the process is continuing. Modifications of Injection moulding process is the next step which has evolved world-wide & is finding foot-hold in India. Expectations of Engineering industries can be met by injection moulded products based on PP. In days to come due to low monomer cost of PP as compared to other injection moulding materials, usage of PP will be beneficial to all. Team-work of end-users, designers, processors & material manufacturers essential for continuous innovations. Sept 27, 2007 IPI Windsor Endowment Lecture

45 Sept 27, 2007 IPI Windsor Endowment Lecture