Plastic Molding Comparison

In manufacturing, molding refers to the process of shaping material into a rigid form. Pexco is the North American Leader in plastic molding, offering our customers a variety of techniques and materials to best meet their needs.

Choosing the appropriate molding process for manufacturing plastic parts depends on several factors, including the design, size, complexity, production volume, and material properties required. Here’s an overview of when to use each type of molding:

Plastic Injection Molding

Plastic Injection Molding is a process that involves heating a polymer above its melting point and then injecting the molten resin into a mold.

  • High-Volume Production: Ideal for producing large quantities of identical parts.
  • Complex Geometries: Suitable for intricate designs with detailed features and tight tolerances.
  • Material Variety: Can be used with a wide range of thermoplastic and thermosetting polymers, such as FEP, PFA, PAI (Torlon®), Peek, and PEI (Ultem®).

Blow Molding

Blow molding is the forming of a hollow object by inflating or blowing a molten polymer into the outside shape of the mold.

  • Hollow Parts: Best for making hollow objects, such as bottles and containers.
  • Medium to High Production Volumes: Economical for large production runs in materials such as HDPE, PP, PETG and PC.
  • Lightweight Products: Ideal for products where weight reduction is important.

Compression Molding

Compression Molding is a process that uses heat, pressure, and time to shape pre-measured materials into parts with various lengths, thicknesses, and complexities.

  • Large, Flat, or Curved Parts: Suitable for producing large and relatively simple parts.
  • Thermosetting Materials: Commonly used for thermosetting plastics and composites such as silicone, polyurethane and phenolic.
  • Low to Medium Production Volumes: Effective for lower production volumes than injection molding.

Extrusion Molding

Extrusion molding is used to form plastic materials into pre-defined shapes.

  • Suited for long, hollow formed applications.
  • Continuous Profiles: Best for creating long continuous shapes with a consistent cross-section in materials such as acrylic, polycarbonate, PVC and polyethylene.
  • High Production Volumes: Economical for high-volume production of parts.

Rotational Molding

Rotational molding is a technique that creates hollow plastic parts of any size. A hollow mold is filled with powdered resin, and the mold rotates bi-axially and then is transferred to an over.  The mold continues to rotate as the resin melts and coats the wall of the mold.

  • Relatively low-cost tooling.
  • High durability, stability, and strength using materials such as LDPE, HDPE, PP and PO (nylon).
  • Fine-detail surface textures, symbols and/or lettering

Thermoforming

Thermoforming is the process a heating a thermoplastic sheet or block to its softening point.  The items are then stretched across a single-sided mold and manipulated into the desired shape.

  • Flexibility and low cost of entry
  • Durability, color and texture options using materials such as ABS, HDPE, PVC, and PC.
  • Sustainability

Choosing the right molding process depends on the project’s specific requirements, including its design, material, production volume, and cost considerations. Each method offers distinct advantages that make it suitable for different applications.

Pexco offers expertise in material engineering, materials and processing and can assist you in choosing the best process for your project.  Pexco processes over 500 different materials including FEP, PFA, PAI, PEEL, PPS, PEI, acrylic, polycarbonate, PVC and polyethylene, and can help you find the best fit for your next project.

For more information on these processes, materials, or how Pexco can help you with your project, please contact Rich Reed, Vice President of Sales – Custom, at [email protected] or visit our website at www.performanceplastics.com.

 

 

What material is best for my project?

 

Thermoplastics, elastomers, and thermosets are three distinct classes of polymers, each with unique properties and characteristics.  How do you know which one is best for your project?

Thermoplastics:

  • Definition: Thermoplastics are polymers that become pliable or moldable when heated and solidify upon cooling. This process can be repeated multiple times without significant degradation.
  • Behavior: They soften when heated and can be reshaped or remolded, making them highly versatilefor manufacturing processes like injection molding, extrusion, and 3D printing.
  • Properties:
    • They typically have good impact resistance and mechanical strength, depending on the specific type.
    • Examples include polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC).
    • They are recyclable and often used in a wide range of applications from packaging and consumer goods to automotive parts and medical devices.

Elastomers:

  • Definition: Elastomers are polymers that exhibit elastic properties, meaning they can return to their original shape after deformation when the applied stress is removed.
  • Behavior: They are characterized by their ability to stretch significantly and then retract to their initial shape, due to the cross-linked polymer chains.
  • Properties:
    • They have excellent elasticity, resilience, and fatigue resistance.
    • Examples include natural rubber, silicone rubber, and polyurethane elastomers.
    • Elastomers find applications in seals, gaskets, tires, footwear, and various vibration dampening components.

Thermosets:

  • Definition: Thermosets are polymers that undergo a chemical reaction (often called curing or cross-linking) during processing, leading to a permanently set shape.
  • Behavior: Once cured,thermosets cannot be remolded or reshaped by heating, as they undergo a chemical change that irreversibly hardens them.
  • Properties:
    • They typically have excellent dimensional stability, high temperature resistance, and chemical resistance.
    • Examples include epoxy resins, phenolic resins, and polyurethane thermosets.
    • Thermosets are commonly used in applications requiring durable and heat-resistant materials such as in electronics, aerospace, automotive parts, and in household appliances.

Key Differences:

Response to Heat:

  • Thermoplastics: Soften with heat and can be reshaped.
  • Elastomers: Can stretch and return to their original shape due to elasticity.
  • Thermosets: Hardenirreversibly with heat or chemical curing.

Recyclability:

  • Thermoplastics: Generally recyclable.
  • Elastomers: Recycling potential varies; some can be recycled.
  • Thermosets: Difficult to recycle due to their irreversible curing process.

Applications:

  • Thermoplastics: Widely used in consumer goods, packaging, and automotive industries.
  • Elastomers: Commonly found in seals, tires, and flexible components.
  • Thermosets: Used in applications requiring heat resistance and durability, such as electronics and aerospace.

Understanding these differences helps inselecting the appropriate polymer for specific engineering, manufacturing, orproduct design needs based on properties like flexibility, durability, and recyclability.

Performance Plastics, a Pexco Company, has experts in material engineering that can assist you in choosing the best material class for your project.

Fort more information on any of these materials, or how Pexco can help you with your custom project, please contact Rich Reed, Vice President of Sales – Custom, at [email protected] or visit our website at www.performanceplastics.com

JOHNS CREEK, GA (June 5, 2024) – Pexco LLC, a leading North American specialty plastics processor, is pleased to announce the acquisition of the Wallingford, CT facility of Clayens. The Wallingford site, known for its dedicated high-performance plastic CNC Machining, Milling, Multi-axis Turning, Swiss Machining, Annealing, Vapor Polishing, and Assembly, significantly enhances Pexco’s value added and manufacturing capabilities. The site is ISO 9001-2015 as well as ISO 13485-2016. This acquisition will bolster Pexco’s services in key industries such as Aerospace & Defense, Electric & Infrastructure, Life Sciences, Industry & Equipment, and Semiconductor.

 

Pexco CEO Sam Patel stated, “We are thrilled to welcome the Wallingford team to the Pexco family. This acquisition aligns perfectly with Pexco’s strategic growth plan. The Wallingford facility’s advanced machining capabilities and its expertise in critical industries will enhance our ability to meet and even exceed customer requirements. We look forward to integrating the talents and capabilities of the Wallingford team into the Pexco team.”

 

Mike Kane, General Manager at Wallingford, added, “Joining Pexco presents an exciting opportunity for us to leverage Pexco’s scale, reputation, and engineering expertise. We are eager to contribute to Pexco’s broad array of services and solutions, and to expand the reach of our precision machining capabilities across more industries and geographies.”

 

The Wallingford facility was started in 1980 as Connecticut Plastics and was acquired in 2023 by Clayens, a company that was founded in Lyons, France in 1931. It now joins Pexco as part of Pexco’s strategic expansion, marking the addition as Pexco’s 13th location.

 

About Pexco LLC

Based in Atlanta, with multiple plants across North America, Pexco is a leader in the design and fabrication of engineered plastic components. It provides standard and specialty parts and components to manufacturers and end users for a broad range of custom applications, including the specialty industrial, fluid handling, aerospace, life science, traffic safety, lighting, fence, and electrical insulation industries. Pexco offers a full range of custom design, engineering, and fabrication services, with ISO 9001:2015 registration across its manufacturing operations. For more information, visit www.pexco.com or call (770) 872-8013.

 

About Odyssey Investment Partners

Odyssey Investment Partners, with offices in New York and Los Angeles, is a leading private equity investment firm with a more than 25-year history of partnering with skilled managers to transform middle-market companies into more efficient and diversified businesses with strong growth profiles. Odyssey makes majority-controlled investments in industries with a long-term positive outlook and favorable secular trends. For further information about Odyssey, please visit www.odysseyinvestment.com.