BOPP Films, Automotive Bumpers and PP Nonwoven Fabrics Three Case Studies for product and productivity improvements through tailored Additive solutions. INTERFACES ’05, Hungary 15-17 September 2005 Wolfgang Voigt Ciba Specialty Chemicals Inc.
Case Study # 1: Enhance BOPP Properties Challenge: Production of BOPP Films is highly sophisticated and optimized, but faster processing and need to down gage brings PP resins to their limits. Task: Upgrading the efficiency of the Stabilizer systems, in order to meet the requirements of modern process technologies and end use properties
Ciba® IRGASTAB ® BOPP State-of-the-art BOPP Base Stabilization System for superior Processing and Properties
Requirements for Additives In BOPP Film Film processing : Maintain processing window Rework quality Cost effective Film performance : No influence on color Give excellent optical properties No loss of mechanical properties Packaging performance : Organoleptic No change in film shrinkage Maintain surface adhesion/reactivity
BOPP Film Trends BOPP process and film trends : Increasing line speeds (>500m/min) Increasing line width Decreasing film thickness Increasing film modulus Improved organoleptics Improved printability / metallization
BOPP Film Trends PP producers modify polymer structures to meet these requirements : Random copolymers Bimodal PP Stereoregularity, ... Enhanced stabilizer technologies are required to achieve the highest performance Maintain polymer structure Consistent process performance Enhanced film physical properties
IRGASTAB® BOPP for Superior Performance IRGANOX® B215 High Performance Phosphite Blend
Commercial BOPP Film, Reel End Colour IRGASTAB®BOPP(1000ppm) IRGANOX®B215(1500ppm)
Customer confirmation of improved performance…….. Customer Experience Analysis Customer confirmation of improved performance…….. Based on 20 micron film manufactured on 8m stenter. Annual saving estimated to be 4% of manufacturing costs.
Ciba® IRGASTAB® BOPP Is the state-of-the–art Base Stabilization System for BOPP resins, providing significant property and process advantages at a competitive price.
Case Study # 2: Nonwoven Fibers Increasing Line speed Machine Width Challenge: Discoloration of peroxide concentrates and unsatisfactory properties of nonwovens Task: Provide easy-to-use concentrate, enhance nonwoven barrier properties and improve storage
The Novel Polymer Modifier for Polypropylene Nonwovens Ciba® IRGATEC® CR 76 The Novel Polymer Modifier for Polypropylene Nonwovens
Ciba® IRGATEC® CR 76 A novel polymer modifier for PP nonwovens provides Outstanding barrier properties of meltblowns & SMS Enhanced mechanical properties of meltblowns Broader bonding window for spunbond nonwovens Cost saving potential Customer friendly product form and safety in use
Excellent Storage Stability IRGATEC CR 76 5% peroxide 10% peroxide 0h, 80° C 50h, 80° C 500h, 80° C Extrusion: twin screw, l/d = 42, 100 rpm, Tmax = 175° C, 4 kg/h, N2 Peroxide: commercial concentrate based on 2,5-dimethyl-2,5-bis- (tert-butylperoxy)-hexane
Outstanding Meltblown Nonwovens Standard PP MF 25 as raw material for 25 g/m2 meltblown Up to 2 times higher liquid barrier Either 4 times higher tensile or elongation
Controlled Vis-breaking Technology Standard Grade (e.g. MFI 25) IRGATEC CR 76 T = 250°C – 300° C Meltblown Grade (e.g. MFI 1200) Great control of MFI by adjusting either concentration and / or temperature
Ciba® IRGATEC® CR 76 Ames test: not mutagenic (OECD 471) Skin Irritation: not irritant (OECD 404) Skin Sensitization: not sensitizing (OECD 429) Cytotoxicity: no cytotoxic (MEM Elution L929, “Grade 0”) Ciba® IRGATEC® CR 76 Form: Granules Packaging: 2 x 20 kg in box
Case Study # 3: Automotive Bumpers Challenge: Paint curing systems are sometimes interacting with Light Stabilizers: Task: Develop a non interactive system
The Novel, Non-Interactive Light Stabilizer for Automotive Bumpers Ciba® TINUVIN® XT 850 The Novel, Non-Interactive Light Stabilizer for Automotive Bumpers
Key Trends – Exterior (1) Styling of exterior parts make the difference But almost all are painted parts (80%) :
Key Trends – Exterior (2) Or with two-tone bumper fascia (partially painted)
Key Trends - Regulations Increased Aesthetics Durability Degradation controlled up to 10 years More stringent requirements for weatherability. Facilitate future recycling Rationalization of the number of resins used toward PP/TPO Phase-out of PVC in interior applications toward PP/TPO Reduction of VOC (Volatile Organic Compounds) Lower Solvent (1K paint) or waterborne paint systems paint adhesion becomes much more critical
HALS undergoes reactions with acids ... ROO· R=O + ROH R· [Oxidation] R N O O· cyclic stabilization mechanism R N R* R* = - H - CH3 R* H Acid [H+] R N+ X ... TINUVIN® XT 850 does not. -> conventional HALS become ineffective -> acids become ineffective
A paint adhesion success : Customer A Application : Partially painted exterior TPO parts Issue : Poor Paint adhesion as conventional HALS interfere with paint cure in acid-catalyzed 1K systems Solution : Blend based on TINUVIN XT 850 as non-interacting UV system Effect : Durable „two-tone “ TPO bumpers with no paint-adhesion issues Benefit : Made Customer A the leader in partially-painted applications for a regional market
TINUVIN XT 850... avoids paint adhesion failures Stabilizer system Taber scuff [% removed] Aggressive adhesion test 0.4 % Standard HALS 0.2 % UVA 100 % Fail 0.4 % TINUVIN® XT 850 0 % Pass 1- component base coat (acid catalyzed) + 1- component acrylic clear topcoat (acid catalyzed) Samples: 2 mm injection molded plaques Natural reactor TPO contains: 0.05 % CaSt
... outperforms in bright colors Stabilizer system Gloss Retention at 2500 kJ/m² at 3000 kJ/m² 0.4 % Standard HALS 0.2 % UVA 53 % 26 % 0.4 % TINUVIN® XT 850 74 % 70 % Samples: Weathering Conditions: SAE J 1960 PP/EPDM samples contain: 15 % talc + 0.1 % CaSt + 0.075 % IRGASTAB FS 301 color: 0.25 % Pigment Red 177
....... avoids mold deposit XT 850 Tin 791 Simulation of mold deposit caused by reaction with acids: Reaction of additives with stearic acid in hexane: Best performance by TINUVIN XT 850
Summary TINUVIN® XT 850 is the product of choice when non-interacting properties, and low basicity are required, besides very good UV light stability. CIBA® TINUVIN® Xt 850 creates UV weatherable applications for all Polyolefin-based systems in which interactivity can be an issue : Partially-painted parts coated with 1K acidic-catalyzed paints Formulations containing any other acidic components Irganox PS 802 Stearic Acid
Conclusions Development of today’s Plastic Additive solutions is increasingly focused on very specific requirements and applications like helping polymers to keep the pace with state-of-the-art equipment (BOPP Extrusion Line speeds): CIBA IRGASTAB BOPP making polymers fit for new environmental challenges (solvent free paint systems are more critical in terms of adhesion need for non-interactive systems): CIBA TINUVIN XT 850 Modifying polymers for improved properties and higher flexibility in raw materials (better barrier properties, higher storage stability): CIBA IRGATEC CR 76