Plastics Failure

Preface to Second Edition

Acknowledgements

First Edition

Second Edition

Contents

1 A Preliminary Look at the Nature, Causes, and Consequences of Plastics Failure

1.1 Introduction

1.2 Plastics

1.3 Polymers

1.4 Rubbers and Elastomers

1.5 Natural Polymers

1.6 Plastics in the Family of Materials

1.7 Common Features and Differences in Performance or Failure of all Materials

1.8 Unintentional Factors Affecting Failure

1.9 Types and Causes of Failure

1.9.1 When Failure is Not Really a Failure

1.10 The People Factor

1.11 The Consequences of Plastics Failure

1.12 Legal and Financial Aspects of Plastics Failure (see Chapter.9) [3, 34].

1.12.1 Lessons

1.13 References

1.14 Papers by Myer Ezrin and Coauthors on Plastics Failure Analysis, Plastics Analysis, and Related Subjects

1.14.1 Plastics Failure Analysis

1.14.2 Plastics Analysis

1.14.3 Electrical Insulation

1.14.4 Solar Panel Encapsulant Discoloration

1.14.5 Plastics Recycling

2 Fundamental Materials Variables Affecting Processing and Product Performance or Failure

2.1 The Overall Picture

2.2 Polymer Composition [1, 2, 3].

2.2.1 Major Categories of Plastics Composition

2.2.1.1 Thermoplastic and Thermosetting Plastics

2.2.1.2 Thermoplastic Elastomers [3, 7].

2.2.2 Types of Polymers

2.2.2.1 Addition Polymers Based on Vinyl Monomers

2.2.2.2 Thermal and Photolytic Stability of Vinyl Addition Polymers

2.2.2.3 Thermal Analysis in the Study of Polymer Degradation

2.2.2.4 Controlling Thermal Effects in Performance or Failure of Plastics

2.2.2.5 Elastomeric Addition Polymers Based on Diene Monomers

2.2.2.6 Condensation Polymers

2.2.2.7 Other Polymer Types [1, 2, 3].

2.2.2.8 Homopolymers, Copolymers, Terpolymers, and Blends

2.3 Composition—Intentional Additives

2.3.1 Types of Additives (Table.2.3 [9]).

2.3.2 Failure Effects of Intentional Additives

2.3.2.1 Plasticizers

2.3.2.1.1 Adhesion Failure of Vinyl Floor Tiles

2.3.2.1.2 Other Plasticizer-Related Failures

2.3.2.2 Colorants

2.3.2.2.1 Staining of Clothes by Plastic Hangers [4,11].

2.3.2.2.2 Effect of Colorants on Notch Sensitivity

2.3.2.2.3 Poor Mixing of Colorant in Water Filter Canister

2.3.2.3 Flame Retardants

2.3.2.3.1 Omission of Flame Retardants

2.3.2.3.2 Effect on Mold and Part Dimensions

2.3.2.3.3 Effect on a Secondary Part of the Product [11].

2.3.2.3.4 Effect of Frozen-In Stress on Molded Parts Causing Early Failure in Service

2.3.2.4 Unanticipated Effect of Additive

2.3.2.4.1 Enhanced Crystallization Due to a Pigment

2.3.2.4.1.1 Shampoo Tube Screw Caps

2.3.2.4.1.2 The Case of the Shrinking Polyethylene Milk Case

2.3.2.5 Poor Dispersion of Additives—Antioxidant

2.3.2.6 Volatility of Additives—Antioxidant

2.4 Composition—Unintentional Additives

2.4.1 Types of Unintentional Additives

2.4.2 Failure Effects of Unintentional Additives

2.4.2.1 Extraneous Dirt, Lint, and Other Contaminant Materials

2.4.2.1.1 Contaminant from Previous Run in Extruder

2.4.2.2 Residual Monomer, Solvent, or Other Low Level Chemicals

2.4.2.3 Water

2.4.2.3.1 Beneficial Effects of Water Absorbed from the Air

2.4.2.3.2 Hydrolysis of Condensation Type Plastics in Melt Processing

2.4.2.3.3 Appearance Problem Due to Water in Melt Processing

2.4.2.3.4 Voids Formed by Water in Melt Processing

2.4.2.3.5 Water Treeing of Extruded Polyolefin Electrical Power Cables (see Chapter.13, Section.13.5.2.5).

2.4.2.3.6 Shrinkage and Expansion of Moldings

2.4.2.4 Compounding Process Aids in Additives Concentrates

2.4.2.5 Additives in Formulation Ingredients to Improve their Performance

2.4.2.6 Ionic Impurities from Water in Service (Chapter.13).

2.4.2.7 Ionic Impurities in Carbon Black (see Chapter.13).

2.4.2.8 Trace Metal from Extruder Barrel and Screw Coating

2.4.2.9 Impurities in Intentional Additives or Processing Materials

2.5 Molecular Weight (MW)

2.6 Intermolecular Order

2.6.1 Crystallinity

2.6.2 Crosslinking

2.6.3 Orientation Due to Processing

2.6.4 Degree of Fusion

2.6.5 Physical Aging [38–41].

2.7 Combined Effect of Molecular Weight and Crystallinity

2.8 Lessons

2.9 References

3 Failures Related to Design and Material Selection

3.1 Introduction

3.2 Basic and Practical Considerations in Design-Related Failures

3.2.1 The People Factor

3.2.2 Declaring War on Failure

3.2.3 To Test or Not to Test—or How Much is Enough?

3.2.4 The Perfect Design and Product—Does It Exist?

3.2.5 The Prototype

3.2.6 Effect of Design on Processing

3.2.7 Design Checklist

3.2.8 The Most Common Mistakes in Design of Plastics

3.2.8.1 Creep (see Section.3.2.16).

3.2.8.2 Stress (see Chapter.5, Section.5.6.1; Chapter.7, Section.7.6, 7.7).

3.2.8.3 Hostile Environment

3.2.8.4 Shrinkage

3.2.8.5 Color Variance

3.2.8.6 Gate Marks

3.2.8.7 Inadequate Draft

3.2.8.8 Sink Marks

3.2.8.9 Unanticipated Use

3.2.8.10 Time

3.2.9 Product Specifications

3.2.9.1 Materials

3.2.9.2 Design Specifications

3.2.9.3 Performance Specifications

3.2.10 Design for Service Life and Service Conditions

3.2.11 The Hazards of Simultaneous Service Factors

3.2.12 Brittle Fracture—A Balancing Act of Design and Material

3.2.12.1 The Ductile to Brittle Transition

3.2.12.2 Molecular Weight (MW) and Brittle Fracture

3.2.13 Comparison of Plastics and Metals [15].

3.2.14 Crack Phenomena in Fracture

3.2.15 Failure by Fatigue [24–27] (see Section.7.5.3).

3.2.15.1 Fatigue Failure by Crack Propagation

3.2.15.2 Failure by Softening Due to Hysteretic Heating

3.2.15.3 Effect of Environment

3.2.16 Failure by Creep

3.2.16.1 Fundamentals of Creep Behavior

3.2.16.2 Tests to Predict Creep Behavior

3.2.16.3 A Case Study of Creep Failure (see Section.3.2.20, Weld Lines).

3.2.16.4 Creep Failure of a Thermoset Polymer

3.2.17 Failure by Impact (see Chapter.7, Section.7.5.5).

3.2.17.1 Design Effects

3.2.17.1.1 Case Study of a Design Failure

3.2.17.2 Material Effects [31].

3.2.17.3 Molding Effects [31].

3.2.17.4 Molecular Weight (MW) Effects [32].

3.2.17.5 Polymer Composition and Crystallinity Effects

3.2.18 Electrical Stress [33, 36] (see Chapter.13).

3.2.19 Surface Effects in Failures Related to Design

3.2.20 Weld Lines

3.2.20.1 Examples of Weld Line Failures and Effects

3.2.20.1.1 Case Studies of Weld Line Failures

3.2.21 Warpage

3.3 Lessons

3.4 References

4 Examples of Failure Due to Design and Material Selection

4.1 Introduction

4.2 Part or Product Design

4.2.1 Examples of Failure Due to Design and/or Material

4.2.1.1 Mold Design Problems

4.2.1.1.1 The Replacement New Mold that Failed [22].

4.2.1.1.2 Fracture of Ultrasonically Welded ABS Part Due to Mold Design Problem [27].

4.2.1.1.3 Fracture of Plastic Parts in Water Service Due to a Mold Problem [28].

4.2.1.2 Water Service Failures Not Related to a Mold Problem

4.2.1.2.1 Fracture of a Toilet Connector Nut at an Abrupt Wall Thickness Change [29].

4.2.1.2.2 How to Turn a Threaded Part Inside Out [22].

4.2.1.2.3 Toilet Valve Design [22].

4.2.1.2.4 Water Filter Design [22].

4.2.1.2.5 Elbow Coupling Design [22].

4.2.1.2.6 Plastic Failure Because of a Metal Failure [22].

4.2.1.3 Processing-Related Failure Due to Design

4.2.1.3.1 Spin Welding of a Water Filter [22].

4.2.1.3.2 A War-Material Process Problem [30, 31].

4.2.1.4 Failure Due to a Metal Component of a Part

4.2.1.4.1 Plastic Over Metal—The Fractured Kitchen Blender [32].

4.2.1.4.2 Metal Inserts (see Chapter.3, Section.3.2.13).

4.2.1.5 Design Based on Metal Design—Bad News [1].

4.2.1.6 Attachment Stresses—Fracture of Bosses Attaching Motor Housing to Lawnmower [35].

4.2.1.7 Failure Due to Static Load Imposed by Screws and Rivets

4.2.1.7.1 Cracks at Molded-In Holes

4.2.1.7.2 Cracks at Screw Holes Drilled into Plastic Sheet

4.2.1.8 Stress Concentration at a Weak Point

4.2.1.8.1 Weld Lines (see Chapter.3, Section.3.2.20) [38–41].

4.2.1.8.1.1 Fracture of ABS Syringe Needle Holder with Flats Close to Weld Lines (see Section.7.3.2.1.3, Figs. 7.5, 7.6).

4.2.1.8.2 Externally Applied Stress

4.2.1.8.2.1 Failure to Consider Occasional Impact in Design of Umbrella

4.2.1.8.2.2 Fracture at Gate of PP Antiperspirant Bottle Cap Located at High Stress Location Where Cap is Tightened [27].

4.2.1.8.2.3 Microwave Oven Door Handle Screw Located at Point of High Stress When Door is Opened

4.2.1.8.3 Internal Stress Due to Design

4.2.1.8.3.1 Poor Design and Stress Concentrations in Automobile Coolant Reservoir Tank [42].

4.2.1.8.3.2 Stresses in Interference Fit—Fracture of Nylon Head Harness Inside Hard Hat [43].

4.2.1.9 Poor Design

4.2.1.9.1 Multiple Modes of Failure of a Poorly Designed PS Pitcher [35].

4.2.1.9.2 Flexible Hinges Require Special Design—Polyethylene Soap Dish

4.2.1.9.3 Fracture of Pultruded E-Glass Rod Due to Retention of Atmospheric Liquid in Cuplike Design of Metal End Fitting (see Section.6.3.9, Fig..6.19, and Section.10.5.1.2).

4.2.1.10 Problems of Design Diagrams

4.2.1.10.1 Misleading or Unwise Instructions in Design Diagrams

4.2.1.10.2 Make Dimensional Specifications Realistic—The Overspecified Part

4.2.1.11 Warpage (see Chapter.3, Section.3.2.21).

4.2.1.12 Failure to Allow for Contraction of PBT Part Due to Thermal Aging [27] (see Chapter.7, Section.7.4.3.2.2, Fig..7.8).

4.3 Failures of Various Types of Plastics

4.3.1 Flexible Polyvinyl Chloride (PVC)

4.3.1.1 Fracture or Tearing Due to Flexural Fatigue

4.3.1.2 Failure in the Flexible Sheet Itself

4.3.1.3 Failure in Products with Attached Parts

4.3.2 Rigid PVC

4.3.2.1 Pipes and Fittings (see Chapter.11).

4.3.2.2 Failure Due to Excessive Heating in Service

4.3.2.3 Failure of PVC Container [22].

4.3.3 Styrenics—PS, Impact PS (HIPS), ABS, SAN

4.3.3.1 PS Homopolymer

4.3.3.2 HIPS

4.3.3.2.1 How Not to Design a Plastic Parking Permit

4.3.3.3 ABS—Acrylonitrile Butadiene Styrene Terpolymer

4.3.3.4 SAN—Styrene Acrylonitrile Copolymer

4.3.4 Polyolefins

4.3.5 Polyethylene PE

4.3.5.1 Two Stresses Applied Simultaneously (see Chapter.3, Section.3.2.11; Chapter.6, Section.6.3.1.3).

4.3.5.2 Environmental Stress-Cracking

4.3.5.2.1 Stress-Cracking of Water Pail

4.3.5.2.2 Aerators in Sewage Treatment Lagoon

4.3.5.2.3 Drop Impact Bottle Fracture

4.3.5.2.4 Fracture of Hair Cream Screw Cap

4.3.5.2.5 Fracture of Lawnmower Belt Cover Hold-Down Tab

4.3.5.2.6 Extensive Cracking of a Medium Density Polyethylene Cover

4.3.5.3 Electrical Water Treeing (see Chapter.2, Section.2.4.2.3.5; Chapter.13—Figs. 13.15 and 13.16 illustrate this type of failure of PE).

4.3.5.4 Service Beyond Design Limits

4.3.5.5 Design and/or Material Selection

4.3.5.6 Oxidative Degradation

4.3.5.6.1 Cracked Barrel Cover

4.3.5.6.2 Flashlight On-Off Switch

4.3.5.6.3 Falling Houseplant Leaves

4.3.6 Polypropylene

4.3.6.1 Shrinkage Out of Control Due to Colorant

4.3.6.2 The Tilted Pancake Syrup Bottle

4.3.6.3 Broken Hair Curlers

4.3.6.4 Fracture of PP Fibers in Artificial Stadium Grass

4.3.6.5 Failure of TV Cabinets During Transport [14].

4.3.6.6 Polypropylene Parts Made Brittle by Too Much Colorant

4.3.7 Ethylene Copolymers

4.3.8 Thermoplastic Engineering Resins that Failed Because Tg Was Too Low for the Service Requirements or Due to Creep—PBT (Polybutylene Terephthalate), PPO (Polyphenylene Oxide), PPS (Polyphenylene Sulfide), and Other Thermoplastics [52].

4.3.8.1 Examples of Thermoplastics Failures [52].

4.3.9 Cellulosics

4.3.9.1 The Showerhead Made with Cellulose Acetate Scrap Resin [55].

4.3.10 Acrylics (PMMA)

4.3.11 Nylon

4.3.11.1 Nylon in Automobile Flipper Covers

4.3.11.2 Nylon Floor Polisher Gear

4.3.11.3 Nylon Hinge Cams [22].

4.3.12 Rubber (see Chapter.2, Section.2.2.2.5).

4.3.12.1 Examples of Rubber Failure

4.4 Unexpected and Unauthorized Problems of Material Selection [64].

4.4.1 Unintentional Errors in Formulation or Processing

4.4.2 Unintentional Variability of Lot to Lot Polymer Coating Acceptability [65] (see Chapter.1, Section.1.14.1 [58]; Chapter.7, Section.7.4.3.2.1).

4.4.3 Unexpected Low Adhesion of Coextruded Film (see Chapter.2, Section.2.4.2.5; Chapter.14, Section.14.4.3.2).

4.4.4 Change of Plasticizer Without Authorization [64] (see Chapter.13, Section.13.3.1.3).

4.5 Environmental, Recycling, and Health Aspects of Plastics Failure (see Chapter.16).

4.6 Lessons

4.6.1 Failures Due Mainly to Design

4.6.2 Failures Due to Part Design and/or Material Selection

4.7 References

5 Processing-Related Factors in Failure

5.1 Introduction

5.2 Test Methods to Evaluate a Polymer’s Heat Stability as a Precursor to a Polymer’s Selection for a Product

5.2.1 Thermogravimetric Analysis (TGA)

5.2.2 Differential Scanning Calorimetry (DSC)

5.2.3 Melt Index (Melt Flow Rate) ASTM D1238 [1a].

5.3 Factors and Variables Common to Processing Methods in General

5.3.1 Intentional and Unintentional Steps in Processing

5.3.2 Other Causes of Failure Due to Processing

5.4 Compounding and Mixing

5.5 Fusion

5.6 Processing Methods

5.6.1 Injection Molding

5.6.2 Extrusion

5.6.3 Thermoforming Plastic Film and Sheet

5.6.4 Blow Molding

5.6.5 Rotational Molding

5.7 Improvements in Processing Methods

5.8 Process Control Methods, Troubleshooting, Failure Analysis, and Test Methods

5.8.1 Process Control Methods

5.8.2 Troubleshooting and Failure Analysis

5.8.3 Test Methods

5.9 Secondary Operations

5.9.1 Welding Methods

5.9.2 Punching

5.9.3 Painting and Decorating

5.9.4 Surface Smoothing by Buffing

5.10 Failure Problems Related to Transportation and Installation

5.11 Lessons

5.11.1 General

5.11.2 Compounding, Fusion, and Dispersion

5.11.3 Primary Processing

5.11.4 Secondary Operations

5.11.5 Testing, Quality Control, and Failure Analysis

5.11.6 Transportation, Storage, and Installation

5.12 References

6 Failure Related to Service Conditions

6.1 Introduction

6.2 General Nature and Principles of Service Condition-Related Failure

6.3 Specific Effects and Examples of Service Conditions

6.3.1 Chemical and Solvent Resistance

6.3.1.1 Chemical Reactions

6.3.1.2 Failures Due to Physical Effects in Chemical and Solvent Resistance in the Absence of Stress

6.3.1.3 Chemical Resistance in the Presence of Stress—Environmental Stress-Cracking (ESC) and Stress Corrosion Cracking (SCC)

6.3.1.4 Application Areas with Major Effects on Chemical-Related Failure

6.3.1.5 Air Pollution

6.3.2 Weathering Effects (Outdoor Aging)

6.3.3 Physical Effects of Thermal Conditions in Service

6.3.4 Plastics in Building Materials

6.3.5 Failure Due to Dimensionally Unstable Nature of the Environment of Plastic Products

6.3.6 Mechanical Effects—Wear and Impact

6.3.7 Biological and Medical (see Chapter.12).

6.3.8 Electrical (see Chapter.13).

6.3.9 Failures Due to Unintentional and Unanticipated Service Conditions

6.4 Lessons

6.4.1 General Considerations

6.4.2 Thermal Effects Including Expansion and Contraction

6.4.3 Degradation by Chemical Reaction

6.4.4 Chemical and Solvent Effects other than Chemical Reaction

6.4.5 Mechanical Effects

6.4.6 Electrical Effects

6.4.7 Unintentional and Unexpected Service Conditions

6.5 References

7 Failure Analysis and Test Procedures

7.1 Basic Considerations

7.2 Failure Analysis General Procedures [2, 7, 10–12].

7.2.1 Types of Information Needed

7.2.1.1 Visual Examination and Noninvasive X-Ray Imaging

7.2.1.2 History and Circumstances of Failure

7.2.1.3 Identification of the Product Source and Plastic Type, Grade, and Source

7.2.1.4 Did Failed Product Meet All Specifications as Produced?

7.2.1.5 Fractography

7.2.1.6 Stress Evaluation or Analysis

7.2.2 Failure Analysis Report

7.3 Flowcharts and Checklists

7.3.1 United States Air Force Plan for Composites

7.3.1.1 Examples of Application of the US Air Force Plan for Composites

7.3.2 General Electric Plastics Company Plan for Thermoplastics [5, 6].

7.3.2.1 Examples of Application of the GE Plan for Thermoplastics

7.3.2.1.1 Part Cracking after Ultrasonic Welding [6].

7.3.2.1.2 Part Cracking In-Use, Around a Boss [6].

7.3.2.1.3 Fracture of ABS Syringe Needle Holder

7.4 Analytical and Test Procedures in Support of Failure

7.4.1 Basic Considerations

7.4.2 Categories of Analytical and Test Methods

7.4.3 Materials Characterization

7.4.3.1 Qualitative Identification of Formulation Components

7.4.3.1.1 Chemical Methods (Noninstrumental) of Polymer Identification

7.4.3.1.2 Instrumental Methods of Polymer Identification

7.4.3.1.3 Qualitative and Quantitative Identification of Formulation Ingredients

7.4.3.2 Physical and Chemical Characterization of Polymers

7.4.3.2.1 MW and MWD (see Section.2.5).

7.4.3.2.2 Degree of Crystallinity, Orientation, Fusion, and Crosslinking or Cure

7.4.3.3 Identification of Contaminants and Other Contributors to Failure

7.4.3.3.1 Thermal Desorption/Gas Chromatography/Mass Spectroscopy (TD/GC/MS)

7.4.3.4 Surface Analysis

7.5 Mechanical Test Methods and Material Characteristics of Mechanical Failure

7.5.1 Introduction

7.5.2 Tensile, Flexural, and Compressive Properties

7.5.3 Fatigue Failure and Tests [44, 45] (see Section.3.2.15).

7.5.4 Microscopic Examination of Fatigue and Other Fracture Types

7.5.5 Impact Failure [65] (see Section.3.2.17).

7.5.6 Wear and Abrasion [70, 71].

7.6 Chemical Resistance and Environmental Stress-Cracking (see Section.3.2.11) [71a].

7.7 Stress Analysis

7.8 Nondestructive Testing and Evaluation Methods (NDT or NDE)

7.8.1 Introduction

7.8.2 Ultrasonic Testing

7.8.3 Acoustic Emission [95].

7.8.4 Acoustic Wave Guide

7.8.5 Tomographical Analysis

7.9 Confirming Failure Analysis Conclusions by Demonstrating Response to Service Conditions in Controlled Experiments

7.10 Lessons

7.10.1 Lessons for Failure Analysis (see Sections 7.1–7.3).

7.10.2 Lessons for Analysis and Testing in Connection with Failure Analysis (see Sections 7.4–7.9).

7.11 References

8 Quality Control—Preventive Failure Analysis

8.1 Basic Considerations

8.1.1 Terminology and Concepts of QC, QA, SPC, SQC, TQC, and TQM

8.1.2 Where QA Fits in Corporate Management

8.1.3 QC Past and Present

8.1.4 Preventive Failure Analysis

8.1.5 The Role of People

8.1.6 QC Test Methods and Statistical Methods

8.1.7 Why Materials, Processes, and Products Vary—Random and Nonrandom Variables

8.1.7.1 Random Variables

8.1.7.2 Nonrandom Material Variables

8.1.7.3 Statistical Control

8.1.7.4 Nonrandom Process Variables

8.1.7.5 Graphical Representation of Random (Common Cause) and Nonrandom (Special Cause) Variations [8].

8.1.7.6 Product Quality Control

8.2 QC/QA Systems

8.3 QC Test Methods—General Considerations and Sampling Plans

8.4 QC of Materials to Be Processed

8.4.1 Categories of Materials

8.4.2 Test Methods for Materials in QC Relative to Failure Analysis

8.4.3 Calibration and Reference Standards

8.4.4 Analytical Methods

8.4.4.1 Chemical Composition—To Analyze or Not to Analyze

8.4.4.1.1 The Choice of Methods for QC

8.4.4.1.2 Sampling Considerations

8.4.4.1.3 Thermal Methods of Analysis for Composition

8.4.4.1.4 ASTM Methods

8.4.4.2 Contaminants

8.4.5 Molecular Weight Methods (see Section.2.5).

8.4.6 Crystallinity and Crosslinkability

8.4.7 Rheological Methods

8.4.8 Visual Methods

8.4.9 Mechanical Properties

8.4.10 Beware of Changes During Transportation and Storage

8.5 QC of Materials in Process—Statistical Process Control

8.5.1 Process Control in Injection Molding [5, 7, 24, 25, 69–77].

8.5.2 Process Control in Extrusion [80–85].

8.5.3 Process Control in Compounding [8, 89–92].

8.5.4 Process Control in Blow Molding [83, 96–99].

8.5.5 Process Control in SMC (Sheet Molding Compound) [102–104].

8.5.6 Process Control in Composites

8.5.7 Process Control in Reaction Injection Molding (RIM)

8.5.8 Online Methods of Process Control

8.5.8.1 Infrared Spectroscopy [89, 110–113].

8.5.8.2 Rheology [89, 110, 111, 114–116].

8.5.8.3 Other Online Methods

8.5.9 Process Control Methods Other than Online Methods

8.5.10 Process Control in Pipe Processing (Chapter.11).

8.6 Quality Control of Products

8.7 In-Service QC Testing

8.8 Lessons for QC/QA of Materials, Processes, and Products

8.9 References

9 Legal Aspects of Plastics Product Liability and Failure

9.1 Introduction

9.2 The Harsh Realities of Product Liability

9.3 Basic Legal Aspects of Product Liability

9.4 Common Causes of Failure that Could Result in Litigation

9.4.1 Design-Related Causes

9.4.2 Material-Related Causes

9.4.3 Engineering-Related Causes

9.4.4 Production-Related Causes

9.4.5 Testing-Related Causes

9.4.6 Sales and Customer Service-Related Causes

9.5 Prevention of Legal Problems

9.5.1 Product Liability Control Program—General Considerations

9.5.2 Design and Product Development

9.5.2.1 Hazards Analysis

9.5.2.2 Failure Modes and Effects Analysis (FMEA) and Fault Tree Analysis (FTA) [37, 39].

9.5.3 Testing and Product Evaluation

9.5.4 Record Keeping and Documentation

9.5.5 Engineering and Production

9.5.6 Quality Control

9.5.7 Warranties, Instructions, Warnings, and Claims

9.5.8 Response to Field Failures and Problems

9.6 Product Liability Insurance

9.7 How to Respond to Claims and to Litigation

9.8 The Expert Witness

9.9 Case Studies of Plastics Failure Litigation

9.9.1 Case Studies Involving Personal Injury or Health Problems

9.9.1.1 Recreational Products

9.9.1.1.1 Fracture of a Plastic Boat Seat [58].

9.9.1.1.2 Fracture of a Plastic-Handled Slingshot [59].

9.9.1.2 Packaging Product Failure

9.9.1.2.1 Fracture of Baby Bottle Liner [60].

9.9.1.2.2 Failure to Provide a Childproof Cap [61].

9.9.1.2.3 Loss of Contents During Opening of Cap [8].

9.9.1.2.4 Fracture of Bottle Cap on Drop-Impact [62, 63].

9.9.1.2.5 Food, Odor, and Taste Problems

9.9.1.3 Home Construction and Other Unreacted Monomer Problems

9.9.1.4 Medical Devices (see Chapter.12).

9.9.1.4.1 Incorrect Size of an Implant

9.9.1.4.2 Silicone and Saline Breast Implants (see Section.12.3.3).

9.9.1.4.3 The Fentanyl Transdermal Pain Patch (see Section.12.2.4.1).

9.9.1.5 Electrical Equipment (see Chapter.13).

9.9.1.6 Transportation Products

9.9.1.6.1 Motorcycle Brake Lever [7].

9.9.1.6.2 Blowout of an Automobile Tire [56].

9.9.1.6.3 Detachment of Automobile Radiator Hose Connection [72].

9.9.1.6.4 Leaking of Hot Hydraulic Fluid from Cracked Valve [73].

9.9.1.7 Infant Products—Detachment of a Snap-Fit Baby Seat (see Section.9.3 [16]).

9.9.1.8 Leakage of Polybutylene Pipe for Water Distribution (see Sections 11.4.2.4 (PB) and 11.4.3.1 (Acetal Fittings); Chapter.1 [23] pp..192–194).

9.9.1.8.1 Zylon Antiballistic Service (see Section.10.6.9).

9.9.1.9 Boston’s Big Dig Fatal Epoxy Adhesive Failure (see Section.9.1 and Section.14.4.1.1.1) [76, 77].

9.9.2 Product Quality Litigation

9.10 Lessons from Case Studies

9.11 References

10 Composites

10.1 The Nature and Purpose of Fiber-Reinforced Plastics

10.2 Defects and Flaws and Other Compositional and Design Factors that Affect Failure

10.3 Causes, Modes, and Mechanisms of Failure

10.3.1 Introduction

10.3.2 Short Fiber Reinforced Plastics

10.3.3 Long Fiber Reinforced Plastics

10.3.3.1 Basic Modes of Fracture of Long Fiber Laminated Composites

10.3.3.2 Materials Factors in Failure

10.3.3.3 Design Factors in Failure

10.3.3.4 Manufacturing Defects and Problems Contributing to Failure

10.3.3.5 Service-Related Causes of Failure

10.4 Failure Analysis Procedures for Composites [13, 36] (see Chapter.7).

10.4.1 Materials Characterization

10.4.1.1 Confirmation of Adherence to Specifications

10.4.1.2 Identification of Contaminants

10.4.2 Nondestructive Evaluation (NDE) (see Section.7.8).

10.4.3 Fractography [49].

10.4.4 Stress Analysis [51].

10.5 Examples of Failure of Fiber-Reinforced Plastics

10.5.1 Pultruded Rods

10.5.1.1 Long Composite Suspension Insulator Rods for Electric Transmission Lines

10.5.1.2 Long Guy Strain Insulator Rods for Electric Transmission Systems [54, 55].

10.5.2 Pipe, Tanks, and Vessels (see Chapter.11).

10.5.2.1 Sand-Filled Sewer Lining Materials

10.5.2.2 Large Scale Chemical Process and Storage Equipment

10.5.2.2.1 Overall Experience of Chemical Process Equipment [68].

10.5.2.2.2 Acid Attack on an Elution Column [56].

10.5.2.2.3 Case Histories of Failure of Cylindrical Tanks for Storage Vessels [68, 69].

10.5.2.2.4 Failure of Thermoplastic Lined GRP Tanks [69].

10.5.2.2.5 GRP Tank Failure at a Branch or Opening (Manway)

10.5.2.2.6 Potential Failure Resulting from Cleaning of Tanks with Water Following Exposure to Acid [60].

10.5.2.2.7 Rectangular Tanks With Flat Sides [69].

10.5.3 Effect of Variability of E-Glass Fiber on Failure

10.6 Examples of Failure of Advanced Composites in Air Defense, Aerospace Service, and Antiballistic Service

10.6.1 Delamination of a Glass Fabric/Polyimide Component in Service [80].

10.6.2 Graphite/Polybenzimidazole [73].

10.6.3 Elevator Test Box [75].

10.6.4 Wing Test Box [77].

10.6.5 Wing Section [79].

10.6.6 Carbon Fiber Reinforced Novolac-Epoxy Resin I-Beam [80].

10.6.7 Carbon Fiber/PEEK Peel [81] and Shear [82] Failures

10.6.8 Antiballistic Service (see Section.10.1; Section.2.2.2.6).

10.6.9 Zylon Antiballistic Service

10.7 Problems of GRP Automotive Bodies

10.8 Lessons

10.8.1 Lessons for Long Pultruded Rods (see Section.10.5.1).

10.8.2 Lessons for Glass Fiber Reinforced Composites in Large Volume Applications (see Section.10.5.2).

10.8.3 Lessons for Aerospace Applications (see Section.10.6).

10.8.4 Lessons for Antiballistic Service

10.9 References

11 Pipes and Fittings

11.1 Introduction

11.1.1 Legal and Public Relations Aspects of Pipe and Fittings Failures

11.1.2 The Nature of Pipe and Fittings Materials and Service

11.1.3 Factors Affecting Failure or Service Life

11.1.3.1 Mechano-Chemical Degradation of PE Pipe [97].

11.2 Pipe Failures—Cause and Prevention

11.2.1 The Nature of Failure of HDPE Potable Water Pipe [98].

11.2.1.1 Other Aspects of Failure of HDPE Pipe in Gas and Water Service

11.2.2 Design

11.2.3 Composition

11.2.3.1 Fundamental Materials Aspects

11.2.3.1.1 The Battle Between Antioxidants and Free Radicals [103].

11.2.3.2 Solid Small Particle Contaminants

11.3 Processing, Joining, and Installation

11.3.1 Processing

11.3.2 Joining

11.3.3 Installation

11.4 Service Conditions

11.4.1 Overall Service Failure Experience and Causes

11.4.2 Case Histories of Field Failures

11.4.2.1 Polyethylene Gas Distribution Systems

11.4.2.2 Failure of Large Diameter PE Pipes

11.4.2.2.1 Polyethylene Sewer Pipe [46].

11.4.2.2.2 Failure of Other Large Diameter PE Pipes

11.4.2.3 PE Water Distribution Systems [1–3].

11.4.2.4 PB Water Distribution Systems [1–3].

11.4.2.4.1 Installation Factors in Failure

11.4.2.4.2 Service Condition Factors in Failure

11.4.2.4.3 The Disputed Claim of Oxidative Degradation as the Main or Core Cause of PB Water Pipe Failure [105].

11.4.2.5 PB Large Diameter Water Pipe [48] (see Section.11.2.1, Rapid Crack Propagation).

11.4.2.6 PVC Water Pipe Fracture for Long Distances (see Section.11.2.1, Rapid Crack Propagation).

11.4.2.7 PVDF (Polyvinylidene Fluoride)—Failure at Socket Joints [50].

11.4.3 Case Histories of Small Diameter PE and PB Water System Failures Due to Fittings and Connections

11.4.3.1 Acetal Fittings [1].

11.4.3.2 Pipe Failures Due to Metal Stiffeners Used with Compression Fittings

11.4.3.3 Failures Due to Pullout of Pipe from Compression Fittings [55].

11.4.4 Failures of Improperly Formulated ABS Fittings and Joints Used in DWV Service (Drain, Waste, and Vent)

11.5 Failure Analysis (see Chapter.7; Section.10.4).

11.5.1 Tests to Simulate Surface Embrittlement of PE Pipe Grade Resin

11.5.2 Short-Term Tests for Resin and Pipe Quality

11.5.2.1 Resin Tests

11.5.2.1.1 Polyolefins

11.5.2.1.2 PVC

11.5.2.1.3 CPVC, Chlorinated PVC [106, 107].

11.5.2.2 Pipe Quality Tests

11.5.2.2.1 Processing and Quality Control Tests to Monitor Pipe after Extrusion

11.5.2.2.2 Tests to Detect Surface Oxidation of Inner Walls of Thick Wall HDPE Pipe [38].

11.5.2.2.3 Nondestructive Detection of Flaws and Voids in Pipes [15, 76].

11.5.2.2.4 Testing for Toxicological Safety [77].

11.5.2.2.5 Tests for Long-Term Performance of Pipe (see Section.11.1.3) [12–14].

11.5.3 Tests for Joints and Seals (see Section.11.3.2) [30, 31, 33].

11.6 Lessons for Pipes and Fittings

11.7 References

12 Medical Applications

12.1 Introduction

12.2 Special Requirements and Basic Aspects of Medical Devices

12.2.1 Materials Aspects and Sterilization

12.2.2 Design-Related Problems

12.2.3 Processing-Related Problems

12.2.4 Packaging-Related Problems

12.2.4.1 The Fentanyl Transdermal Pain Patch (see Section.9.9.1.4.3).

12.2.5 Failures Related to Service Conditions

12.2.5.1 Environmental Stress-Cracking (ESC) of Medical Devices

12.3 Examples of Failures and Limitations of Medical Products

12.3.1 Pacemaker Insulation Leads [9, 14–18].

12.3.1.1 Failure of a Heart Defibrillator Due to Electrical Malfunction [54, 56].

12.3.2 Our Bodies’ Moving Joints—Knee, Hip, Shoulder, Elbow, and Hand

12.3.2.1 A Look at Hip and Knee Joints and Their Replacements [60, 61].

12.3.2.2 Cartilage—Nature’s Protector of Joints [59, 62].

12.3.2.3 Ultrahigh Molecular Weight Polyethylene (UHMWPE)—Chemistry’s Substitute for Cartilage [21–26].

12.3.2.4 So What Can Go Wrong? [65].

12.3.2.5 Metal-on-Metal Hip Replacements—A Disastrous “Good Idea” [54, 55, 64].

12.3.3 Silicone [30–33] and Saline [4, 34] Breast Implants

12.3.4 Other Unfortunate Surgical Implant Devices [54].

12.3.5 Cardiovascular Disease of Heart and Blood Vessels

12.3.5.1 So What Can Be Done to Prevent Heart Attack or Stroke?

12.3.5.2 Cardiovascular Stents

12.3.5.2.1 A New Method of Removing Plaque or Blood Clots from Blood Vessels [77].

12.3.5.3 Urethral Stents for Urine Flow

12.3.5.4 Total Artificial Heart Implant [74, 75].

12.4 Lessons from Medical Plastics Experience

12.5 References

13 Electrical and Electronic Applications

13.1 Introduction

13.2 Basic Aspects of Plastics in Electrical and Electronic Applications that Contribute to Failure

13.2.1 Important Properties of Insulating Materials [1].

13.2.2 Important Properties other than Electrical

13.2.3 Color and Appearance

13.3 Low Voltage Electrical and Electronic Applications

13.3.1 Materials-Related Problems

13.3.1.1 Flame-Retardant Formulations Based on Halogen-Containing Polymers and Compounds

13.3.1.2 Hydrogen Evolution in a Two-Part Silicone Adhesive (Section.1.14 [39] Section.4.2).

13.3.1.3 Change of Plasticizer without Authorization (Section.1.14 [39] Section.5.2) (Section.4.4.4).

13.3.1.4 Unexpected Transfer of Plasticizer from Jacket to Insulation (Section.1.14 [66] Section.4.5).

13.3.2 Design-Related Problems

13.3.3 Processing-Related Problems

13.3.4 Service Condition-Related Problems

13.3.4.1 Predictable Failures

13.3.4.2 Unpredictable Failures

13.3.4.2.1 Failures and Fires of Major Home Appliances [66, 67].

13.3.4.3 Failures Due to Improper Installation

13.3.5 Corrosion and High Electrical Resistance Effects of Plastics on Metal Contacts and Other Parts

13.3.6 Encapsulated Applications

13.3.6.1 Semiconductors and Integrated Circuit Devices [23–30].

13.3.6.1.1 Corrosion Effects Due to Ionic Impurities [23–25, 28–30].

13.3.6.1.2 Failure Due to Electrical Overstress

13.3.6.1.3 Failure Due to Fatigue Cracks Resulting from Differences in Coefficient of Thermal Expansion [26, 29, 30].

13.3.6.1.4 Other Causes of Failure and Reduced Performance

13.3.6.1.5 Summary of Failure Mechanisms [30].

13.3.6.2 Photovoltaic Solar Cell

13.3.7 Telecommunications [10, 34, 35].

13.3.8 Piezoelectric Film [37] and Printed Circuit Boards [38].

13.3.9 Ignition Systems for Small Gasoline Engines

13.3.10 Lithium-Ion Batteries [62, 63].

13.3.11 Fuel Cells [64, 65].

13.4 Fire, Smoke, and Toxicity Effects [7–9].

13.5 Medium and High Voltage Applications

13.5.1 Introduction

13.5.2 Failure Modes and Experience

13.5.2.1 Materials-Related Failures

13.5.2.2 Design-Related Failures

13.5.2.2.1 Unusual Failure of a Power Distribution Cable (Section.1.14 [66]; [69]).

13.5.2.3 Processing-Related Failures

13.5.2.4 Service Condition-Related Failures

13.5.2.5 Water Treeing (see Section.2.4.2.3.5).

13.5.2.6 Unforeseen Effects Experienced in Thermal Overload Testing

13.5.2.7 Failures of Cable Jackets

13.6 Lessons

13.6.1 General for Electrical/Electronic and Low Voltage Applications

13.6.2 Medium and High Voltage Applications

13.6.3 Appliance Failures and Fires

13.7 References

14 Adhesion Failure of Plastics

14.1 Introduction

14.2 Types and Causes of Adhesion Failure

14.3 Analytical and Test Methods for Adhesion Failure Analysis

14.4 Material and Design Aspects of Adhesion Failure

14.4.1 Formulations and Design

14.4.1.1 Design

14.4.1.1.1 Boston’s Big Dig Fatal Epoxy Adhesive Failure (Section.1.14, [41]) (Section.6.3.9; Section.9.1).

14.4.1.2 Silicones: A Two Part Adhesive

14.4.1.3 Hydrogen Evolution by Silicones

14.4.1.4 Curing with Ultraviolet Light

14.4.1.5 Failure Due to Improper Mixing

14.4.1.6 Examples of Adhesion without Using an Adhesive

14.4.1.7 Failure of Light-Curing Acrylics and Cyanoacrylates to Cure

14.4.1.8 Coupling Agents for Composites Bonding

14.4.1.9 Print Adhesion Problem of Recycled Silicone-Coated Paper

14.4.2 Intentional Additives

14.4.3 Unintentional Additives

14.4.3.1 Compounding Process Aids

14.4.3.2 Silicone Oil on Titanium Dioxide Powder

14.4.3.3 Identification of Contaminants Causing Adhesion Failure

14.4.3.4 Identification of Contaminants by GC/MS

14.4.4 Foreign Contaminants

14.4.4.1 Further Cases of Identification of Contaminants

14.4.4.2 An Unusual Case of Failure Due to Plasticizer

14.4.4.3 Failure Due to Polymeric Contaminant as Processed

14.5 Processing Aspects of Adhesion Failure

14.5.1 Surface Condition

14.5.1.1 Bonding of Conductor to Electrical Insulation

14.5.1.2 Surface Roughening to Achieve Bonding

14.5.1.3 Effect on Adhesion of Surface Contamination in Storage

14.5.1.4 Contamination Carried by Spraying

14.5.2 Other Considerations

14.6 Service Conditions

14.6.1 Expansion and Contraction Effects on Adhesion

14.6.2 Moisture Effects on Bond Strength

14.7 Failures Due to Mechanical Effects of Materials Being Bonded

14.7.1 Surface Film Thickness Effect on Adhesion

14.7.2 Warping of Bonded Systems

14.8 Metal-to-Polymer Adhesion Problems

14.8.1 Separation of Insulation from Conductor Due to Shrinkage

14.8.2 Adhesive Failure of Impact PS to Metal

14.8.3 Adhesion of PC to Lead with Epoxy Resin

14.8.4 Bonding of Metal to Ethylene Vinylthioacetate Side Groups

14.9 Unwanted Adhesion

14.9.1 Prevention of Bonding of Stacked Parts with Antiblocking Agent

14.9.2 PVC Plasticizer Became an Adhesive

14.9.3 Unwanted Adhesion Due to Poor Control of Lubricant Level

14.9.4 Binding of Servo Motor Due to Plastic Shrinkage

14.9.5 Servo Motor Failure Due to Degradation of Grease

14.10 Lessons for Adhesion Failure

14.11 References

15 Failure of Human Biopolymers

15.1 Introduction

15.2 Materials

15.2.1 Chemical Composition and Structure

15.2.1.1 Polysaccharides

15.2.1.2 Polypeptides (Proteins)

15.2.1.2.1 Collagen

15.2.1.3 Polynucleotides

15.2.1.4 Lipids

15.3 Design

15.4 Processing

15.4.1 Free Radicals and Antioxidants

15.4.2 Pollutants

15.5 Service Conditions

15.6 Examples of Illnesses Involving Human Biopolymers

15.6.1 Hereditary Illnesses ([1], p..1146).

15.6.1.1 Tay-Sachs Disease

15.6.1.2 Sickle Cell Anemia

15.6.1.3 Hemophilia

15.6.1.4 Muscular Dystrophy

15.6.2 Nonhereditary Illnesses ([1], p..1146).

15.6.2.1 Examples

15.6.2.2 HIV/AIDS

15.6.2.3 Multiple Sclerosis

15.6.2.4 Diabetes

15.6.3 Illnesses Involving Free Radical Damage (see Section.15.4.1).

15.6.3.1 Free Radicals

15.6.3.2 Antioxidants

15.6.3.3 Free Radicals Produced in Metabolism

15.6.3.4 Free Radicals From Radiation

15.6.3.5 Molecular Changes Due to Free Radicals

15.6.3.6 Antioxidants in Human Biopolymers

15.6.4 Glycation—The Process (see Sections 15.2.1.2.1, 15.6.4.1).

15.6.4.1 Illnesses Due to Reaction of Sugars with Proteins (Glycation) [26, 27].

15.6.5 Aging, Cancer, and Cardiovascular Illnesses

15.6.5.1 Aging (See Section.15.6.4, Glycation).

15.6.5.1.1 Skin

15.6.5.1.2 Knee and Hip Joint Replacement and Bone Fracture (See Section.12.3.2.1).

15.6.5.1.3 Heart Attack and Stroke

15.6.5.1.4 Alzheimer’s Disease

15.6.5.1.5 Gray Hair

15.6.5.1.6 Benign Prostatic Hyperplasia (BPH)

15.6.5.1.7 Frequency of Urination (Bladder Elasticity)

15.6.5.1.8 Dry Eyes (Keratoconjunctivitis Sicca) [34a, 34b].

15.6.5.2 Cancer

15.6.5.3 Heart, Stroke, and Cardiovascular System

15.7 Lifestyle Choices

15.7.1 “Eating Right”

15.7.2 Exercising

15.8 Synthetic Polymers Designed to Help Cure Illnesses Involving Human Biopolymers

15.8.1 Dendrimers and Hyperbranched Polymers [63–65].

15.8.2 Conducting Polymers [63].

15.8.3 Polymers that Imitate Biology [69–71].

15.8.4 Polymers for Tissue Engineering [72, 73].

15.8.5 Synthetic Genetics—Artificial Genes

15.8.6 Nanopolymers [75].

15.9 Lessons for Failure of Human Biopolymers

15.10 References

16 Environmental, Recycling, and Health Aspects of Plastics Failure

16.1 Introduction

16.2 Recent Trends Contributing to the Problem

16.2.1 Are Plastics “The Next Lead” [19]?

16.3 Historical Background of Recycling, Environmental, and Health Concerns

16.3.1 Monomers and Solvents

16.3.2 Food and Drug Administration and the Delaney Clause [21].

16.3.3 Heavy Metal Compounds

16.3.4 Asbestos

16.3.5 Polyvinyl Chloride (PVC)

16.3.5.1 Dioxin Aromatic Chlorine Compounds Formed on Burning PVC

16.3.5.2 Hydrogen Chloride and Mercury

16.3.5.3 Phthalate Plasticizers for PVC

16.3.6 Toxicity of Monomers and Additives Relative to That of Polymers

16.3.7 Recycling

16.3.8 The McDonald’s Experience

16.4 Legal Actions and Regulatory Requirements of Plastics

16.4.1 Bisphenol.A and Phthalate Plasticizers

16.4.1.1 Legal and Regulatory Action Regarding Bisphenol.A (BPA) [58–72].

16.4.1.2 Legal and Regulatory Action Regarding Phthalates

16.4.2 Flame Retardants

16.4.3 RoHS and WEEE in Europe—Hazardous Waste Disposal of Electronic and Electrical Equipment

16.4.4 RCRA and HSWA Federal Regulations in the USA and Individual State Regulations

16.4.5 Recycling of PE and PET

16.4.6 Recycling of Multimaterial Products [36b].

16.5 Monomer Problems in Polymerization

16.5.1 ABS (Acrylonitrile/Butadiene/Styrene)

16.5.2 Formaldehyde Condensation Polymers

16.6 Plasticized PVC Baby Toys and Medical Products

16.7 Chinese Toys [42a].

16.8 Monomer, Additive, and Degradation Aspects of Food Packaging

16.8.1 Unpolymerized Monomer

16.8.2 Polystyrene

16.8.2.1 Differing Opinions of Environmental and PS Industry Groups on Health Hazards

16.8.2.2 Foam Polystyrene

16.8.3 The FDA Position on Microwave Food Applications of Plastics

16.8.4 The FDA Position on DEHA Plasticizer (Diethylhexyl Adipate) and Dioxins

16.8.4.1 The Position of Consumer Groups on DEHA in PVC Cling Wraps

16.8.5 British Studies of Styrene, Benzene, and Other Materials in Plastics Packaging and Foods

16.8.6 Teflon—Polytetrafluoroethylene

16.9 Pollution of Oceans and Waterways by Discarded Plastic Waste

16.10 Lessons for Environmental, Recycling, and Health Aspects of Plastics Failure

16.11 References

Subject Index by Chapter

Subject Index