Injection Molding Plastic Materials RJC Use

Injection Molding Plastic Materials RJC Use

ABS (Acrylonitrile Butadiene Styrene)

ABS Injection Molding plastics provide a balanced combination of mechanical toughness, wide temperature range, good dimensional stability, chemical resistance, electrical insulating properties, and ease of fabrication. ABS plastic is available in a wide range of grades including medium and high-impact, heat-resistant, plateable fire-retardant, and both low and high gloss varieties.

Applications: Computer housings, small appliances, automotive interior trim, and medical components

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

5000-7500 psi 270,000-380,000 psi 3.0-7.5 ft-lb/in notched izod 140°-200° F Poor to Fair

Advantages
- Good impact resistance with toughness and rigidity
- Metal coatings have excellent adhesion to ABS
- Excellent processability and appearance
Disadvantages
- Poor solvent resistance
- Low dielectric strength (not a good insulator)
- Low continuous service temperature (melts easily)
ABS + PC (ABS + Polycarbonate Alloy)

PC + ABS Injection Molding plastics offer improved strengths over ABS at a lower cost than Polycarbonate. Exceptional low-temperature Impact Strength. The Injection Molding Plastic material can be modified by the addition of glass fiber, mineral fillers, and flame retardant. Applications: Automotive exterior and interior components, medical hardware, electrical housings, computers, monitors, business equipment housings, and enclosures

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

6400-9150 psi 300,000-400,000 psi 8-12 ft-lb/in notched izod 140°-210° F Poor to Fair

Advantages
- Good impact resistance with toughness and rigidity
- Metal coatings have excellent adhesion to ABS
- Very good indoor UV light color stability
- Excellent processability and appearance
Disadvantages
- Poor solvent resistance
- Low dielectric strength (not a good insulator)
- Low continuous service temp. (melts easily)
Acetal (POM) (Polyoxymethylene)

Acetal Injection Molding Plastic is semi-crystalline. They offer excellent inherent lubricity, fatigue resistance, and chemical resistance. Acetals suffer from outgassing problems at elevated temperatures and are brittle at low temperatures. Glass-filled and added lubrication grades are available, flame retardant grades are not.

Applications: Mechanical Automotive, Business Machine, and Household Appliance, Components i.e. Slides, Gears, Cams, Bushings, Door Handles and Seat Belt Parts.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

6000-22,000 psi 120,000-170,000 psi .8-2 ft-lb/in notched izod 180°-300° F Excellent

Advantages
- High tensile strength with rigidity and toughness
- Good impact and solvent resistance
- Glossy molded surface
- Low static and dynamic coefficients of friction (slippery)
- Many grades have FDA and NSF approvals on food and water contact
- Replace die-cast metal components
Disadvantages
- Difficult to bond bond
- Poor resistance to acid and bases
- Subject to UV degradation
Acrylic (PMMA) (Polymethyl methacrylate)

Acrylic PMMA is a tough, highly transparent Injection Molding Plastic material with excellent resistance to ultraviolet radiation and weathering. It can be colored, molded, cut, drilled, and formed. Acrylic is an economical alternative to polycarbonate (PC) when extreme strength is not necessary. It is often preferred because of its moderate properties, easy handling and processing, and low cost, but behaves in a brittle manner when loaded, especially under an impact force.

Applications: Automotive Transparent Items such as Head/Tail Lenses and Trim, Household Light Fixtures and Decorative Items, Safety Equipment and Shields.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

2800-10,9000 psi 221,000-534,000 psi .22-1.1 ft-lb/in notched izod 183°-217° F Excellent

Advantages
- Excellent optical clarity
- Excellent weather ability and resistance to sunlight
- Rigid with good impact resistance
- Good light transmission
Disadvantages
- Poor solvent resistance
- Subject to stress cracking
- Slightly absorbs moistures
- Continuous service temp. (melts easily)
Nylon 6-PA (Polyamide)

Nylons are semi-crystalline Injection Molding Plastics with a good range of properties. Nylons are widely used because they have a good cost to performance ratio. Lower numbered nylons, 6,6-6, 4-6, absorb moisture and change their properties as a result. Nylons have been compounded with reinforcements, fillers, and additives to produce a very wide variety of properties. Nylon 6 has the lowest modulus of all nylon grades.

Applications: Automotive components, Bearings, Electronic Connectors, Gears, Consumer Products, and Industrial products.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

6,000-24,000 psi 390,000-1,100,000 psi 2-8 ft-lb/in notched izod 200°-350° F Good to Excellent

Advantages
- Temperature capability 600°-700° for short term
- Excellent chemical resistance
- High resistance to abrasion
- Tough and withstands repeated impact
Disadvantages
- Absorbs moisture (can affect the electrical and mechanical properties)
- Requires UV stability
- Attacked by strong acids/bases
- High notch sensitivity
Nylon 6/6-PA (Polyamide)

Nylons are semi-crystalline Injection Molding Plastics with a good range of properties. Nylons are widely used because they have a good cost to performance ratio. Lower numbered nylons, 6,6-6, 4-6, absorb moisture and change their properties as a result. Nylons have been compounded with reinforcements, fillers, and additives to produce a very wide variety of properties. Nylon 6-6 offers better properties than nylon 6 without being as costly as nylon 4-6. It has the best abrasion resistance of all nylons. Verton, long glass fiber-filled materials, by LNP, are excellent metal replacement materials.

Applications: Automotive components, electronic connectors, gears, consumer products, and industrial products.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

8,000-24,000 psi 430,000-1,100,000 psi 2-8 ft-lb/in notched izod 220°-350° F Good to Excellent

Advantages
- Temperature capability 600°-700° for short term
- Excellent chemical resistance
- High resistance to abrasion
- Tough and withstands repeated impact
Disadvantages
- Absorbs moisture (can affect the electrical and mechanical properties)
- Requires UV stability
- Attacked by strong acids/bases
- High notch sensitivity
PBT Polyester (Polybutylene Terephthalate)

PBT polyesters are semi-crystalline. They are versatile Injection Molding Plastic materials with a good range of properties. They have excellent electrical properties and are abrasion-resistant. PBT has been extensively compounded giving a very wide range of properties. PBT performs much like Nylon but can handle higher temperatures and does not absorb moisture. PBT has excellent impact strength but is very notch-sensitive. PBT is very anisotropic in shrinkage, so it is difficult to mold to extremely tight tolerances.

Applications: Industrial equipment applications, business equipment, automotive housings-under the hood, power tool casings.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

6,000-13,000 psi 300,000-1,200,000 psi 1 ft-lb/in notched izod 250°-420° F Fair to Good

Advantages
- Good flow
- Tough
- Hydrolysis Resistant
- High impact
- Easily Processed
Disadvantages
- Low Max. Use temperature
- Lower Stiffness than similar PET
- Lower Strength than similar PET
- Attacked by Strong Bases
PC (Polycarbonate)

Polycarbonate is an amorphous Injection Molding Plastic material with excellent impact strength, clarity, and optical properties. It is very widely used and a wide variety of compounds are available. Polycarbonate has excellent mechanical properties and can be molded to tight tolerances. It is attacked by solvents and petrochemicals, and its wearability is only adequate. Applications: Automotive Headlights, Business Machines, Consumer Products, Telecommunications, Medical Products, and Mechanical Goods.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

9000-23,000 psi 340,000-1,400,000 psi 2-18 ft-lb/in notched izod 150°-300° F Poor to Fair

Advantages
- High impact resistance
- Clarity
- Good flammability performance
- Dimensional stability
- Chemical resistance (PC blends)
Disadvantages
- Only fair solvent resistance
- Subject to stress cracking
- Degrades if not processed correctly
- High processing temperature
- Yellowing after long term exposure to UV light
PEI (Polyetherimide)

PEI is an amorphous, high-temperature Injection Molding Plastic material with relatively low cost compared to other high-temperature materials. It has excellent elongation and Impact Strength and can be molded to tight tolerances. Its chemical resistance is not as good as crystalline materials but is excellent for an amorphous material. PEI behaves similar to polycarbonate but can perform at higher temperatures.

Applications: Commercial aircraft interiors, healthcare products, cooking utensils, fiber optics, electrical and electronic applications.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

14,000-28,000 psi 480,000-1,300,000 psi 2 ft-lb/in notched izod 375°-420° F Fair to Good

Advantages
- High heat resistance
- Exceptional strength and impact modulus
- High dielectric strength
- Broad chemical resistance
- Biocompatible
- Excellent machinability and finishing characteristic
- Outstanding processability on conventional molding equipment
- Flame resistance with low smoke evolution
Disadvantages
- Translucent and opaque-clear is not available
- High cost
- Notch sensitive
- High processing temps required
PE (Polyethylene)

Polyethylene is a widely used, inexpensive, Injection Molding thermoplastic. It has good inherent lubricity and is easy to process. Polyethylene has good to excellent chemical resistance. It is also soft and cannot be used in temperatures much above 150. As a family, they are light in weight and possess toughness, chemical resistance, impermeability as well as excellent electrical insulating properties.

Applications: Consumer products, houseware items, electronic wire/cable insulators, and medical products

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

1900-4500 psi 40,000-105,000 psi 2-No break ft-lb/in notched izod 130°-150° F Good to Excellent

Advantages
- Low Cost
- Impact resistance from -40° to 194° F
- Moisture resistance
- Food grades available
Disadvantages
- Poor weather resistance
- High thermal expansion
- Subject to stress cracking
- Difficult to bond
- Flammable
- Poor temperature capability
LDPE (Low-Density Polyethylene)

Polyethylene is a widely used, inexpensive, Injection Molding thermoplastic. It has good inherent lubricity and is easy to process. Polyethylene has good to excellent chemical resistance. It is also soft and cannot be used in temperatures much above 150. As a family, they are light in weight and possess toughness, chemical resistance, impermeability as well as excellent electrical insulating properties. Low-density polyethylene is the softest and most flexible version of this material. It has high elongation giving it excellent impact strength. This is offset by its permanent deformation upon impact.

Applications: Consumer products, houseware items, electronic wire/cable insulators, and medical products.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

1,200-4,000 psi 35,000-48,000 psi No break ft-lb/in notched izod 130°-150° F Good to Excellent

Advantages
- Low cost
- Impact resistance from -40° to 194° F
- Moisture resistance
- Food grades available
Disadvantages
- Poor weather resistance
- High thermal expansion
- Higher cost
- Subject to stress cracking
- Difficult to bond
- Flammable
- Poor temperature capability
HDPE (High-Density Polyethylene)

Polyethylene is a widely used, inexpensive, Injection Molding thermoplastic. It has good inherent lubricity and is easy to process. Polyethylene has good to excellent chemical resistance. It is also soft and cannot be used in temperatures much above 150. As a family, they are light in weight and possess toughness, chemical resistance, impermeability as well as excellent electrical insulating properties. High-density polyethylene is the hardest and stiffest version of this material. It does not have the impact strength of low density but is more resilient.

Applications: Consumer products, houseware items, electronic wire/cable insulators, and medical products

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

3,200-4,500 psi 145,000-225,000 psi .4-4 ft-lb/in notched izod 130°-150° F Good to Excellent

Advantages
- Low cost
- Impact resistance from -40° to 194° F
- Moisture resistance
- Food grades available
Disadvantages
- Poor weather resistance
- High thermal expansion
- Subject to stress cracking
- Difficult to bond
- Flammable
- Poor temperature capability
PP (Polypropylene)

Polypropylene is a widely used, semi-crystalline Injection Molding Plastic material. It has been extensively compounded to provide a wide range of properties at a wide range of costs. In general, polypropylene is a low-temperature Injection Molding Plastic material with excellent chemical resistance. It has no known solvent at 73 F. Polypropylene is difficult to mold to extremely close tolerances.

Applications: Packaging, industrial components for fluid processing, household goods, automotive and electrical hardware.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

4,500-18,500 psi 210,000 -1,500,000 psi 1.4-5.5 ft-lb/in notched izod 150°-300° F Excellent

Advantages
- Excellent moisture resistance
- Food grades available
- Mold–in hinge possible
- Good impact strength
Disadvantages
- Degraded by UV
- Flammable (retarded grades available)
- Attacked by chlorinated solvents
PPA (Polyphthalamide)

PPA is a relatively new, semi-crystalline Injection Molding Plastic material, with an excellent cost to performance ratio. PPA bridges the performance gap between nylons/polyesters, and higher-priced, high-temperature materials such as PEI and PEEK. PPA has excellent impact strength and is not notch sensitive. PPA does absorb moisture, and its properties change as a result. This change is not nearly as great as 6-6 nylon. Despite its relatively recent introduction, good design data is available for PPA. Applications: Automotive applications, Housing for high-temperature electrical connectors, Multiple other uses as a replacement to metals.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

9,000-33,000 psi 270,000 -2,700,000 psi .6-22 ft-lb/in notched izod 300°-450° F Good to Excellent

Advantages
- Heat resistance
- Chemical resistance
- Can resist infrared soldering environments
- Relatively low moisture absorption
- Strength or physical properties
Disadvantages
- Not inherently flame retardant
- Requires good drying equipment
- High processing temperatures
PPS (Polyphenylene Sulfide)

PPS is a high-temperature semi-crystalline Injection Molding Plastic material. It has good mechanical properties and excellent chemical resistance at elevated temperatures. PPS has been compounded extensively and many different types of properties are available. PTFE-filled PPS is one of the best bearing materials available. Unfilled grades of PPS have poor properties, so components are usually made from glass-filled or glass/mineral-filled grades. PPS is very sensitive to molding conditions and must be processed properly to achieve its maximum potential. Applications: Hydraulic components, bearings, cams, valves, and electronic parts

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

14,000-28,000 psi 550,000 -2,900,000 psi .5-6 ft-lb/in notched izod 450°-500° F Good to Excellent

Advantages
- Capable of extended usage at 450° F
- Good radiation resistance
- Good solvent and chemical resistance
- Excellent dimensional stability
- Flame retardant
- Low water absorption
Disadvantages
- Difficult to process (high melt temps)
- High cost
- Fillers required to obtain good impact strength
- Attacked by chlorinated hydrocarbons
SAN (Styrene Acrylonitrile)

SAN is ABS without the Butadiene. It does not have the Impact Strength of ABS, but can be crystal clear. Injection Molding Plastic, Styrene Acrylonitrile has better general chemical resistance than polystyrene and is cheaper than acrylic. It has a good combination of rigidity, strength, toughness, and transparency. Applications: Battery cases, Dials, Knobs, Switches, Lenses, Trays, Containers, Covers, Autoclavable devices, Dental & Medical light diffusers

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

10,000-18,000 psi 500,000-1,200,000 psi .3-3.0 ft-lb/in notched izod 140°-200° F Poor to Fair

Advantages
- Heat Resistant
- High Clarity
- High Flow and Rigidity
- Dimensionally Stable
Disadvantages
- Low impact strength
- High processing temps
- Flammable-smoke generation
- Yellows quicker than other PS
TPE (Thermoplastic Elastomer)

Thermoplastic elastomers (TPE) are a combination of polymers (usually plastic and rubber) which consist of both thermoplastic and elastomeric properties resulting in a product that is extremely easy to use in manufacturing a variety of products. TPE Injection Molding Plastic requires little or no compounding and no need to add reinforcing agents, stabilizers, or cure systems.

Applications: Automotive Fluid Delivery Systems, Household appliances, Sporting goods, Electrical and Medical components.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

1,000-7,000 psi 5,000-800,000 psi 2.5-No Break ft-lb/in notched izod 200°-300° F Fair to Good

Advantages
- Low compression and tension set
- Easily processed
- Fatigue resistance
- Good tear strength
Disadvantages
- Flammable but flame retardant grades available
- Extensive heat aging causes a severe change in mechanical properties
- High cost
TPU (Thermoplastic Polyurethane Elastomer)

Injection Molding Thermoplastic polyurethane elastomers exhibit excellent abrasion and wear resistance and high tensile and tear strengths. TPUs are tough, durable, easy to clean and well-suited to applications that demand the elasticity of rubber combined with high stability. In addition, the inherent translucency of these products makes it easy to color and that is an added benefit in many applications. Applications: Automotive and Aerospace Applications, Medical and Optical purposes, Electrical Wire and Cable Coverings.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance

6960-12,000 psi 260,000-340,000 psi .80-10.1 ft-lb/in notched izod 160°-250° F Fair to Good

Advantages
- Chemical Resistant
- Low temp. flexibility
- Abrasion and wear resistant
- Easily Processed
Disadvantages
- Shorter shelf life
- Lower Stiffness than similar PET
- Drying required pre-processing
- Narrow hardness range

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