Plastic Strapping (PP/PET): A Beginner's Guide

Introduction

Plastic strapping (PP/PET) refers to two widely used types of polymer bands—polypropylene (PP) and polyethylene terephthalate (PET)—employed for securing packages, pallet loads, and bundled goods. These straps are designed to keep items stable during handling and transit, protect product integrity, and improve efficiency in warehousing and shipping operations. For beginners, understanding the differences between PP and PET, how they behave, and when to use each is key to choosing the right strapping for your needs.

What PP and PET are

PP (polypropylene) strapping is a lightweight, flexible, and economical option. It stretches under load and recovers slightly, making it forgiving for lighter loads and irregular shapes. PET (polyethylene terephthalate) strapping is stronger, has low elongation, and behaves more like steel in terms of holding power. PET provides excellent tensile strength and is commonly used where higher load retention is required.

Properties and differences

• Tensile strength: PET generally provides higher tensile strength per width compared with PP.
• Elongation: PP stretches more and absorbs shock better, while PET has low stretch and maintains tension longer.
• Temperature sensitivity: PP is suitable for general use but can be less effective in cold conditions; PET performs well across a wider temperature range.
• Durability: PET resists creep and is more suitable for long-term storage and heavy or palletized loads; PP is suitable for short-term bundling and light cartons.
• Cost: PP is usually the cheapest option; PET costs more but often replaces steel strapping where higher strength is needed.

Common sizes and formats

Plastic strapping comes in various widths (commonly 9mm, 12mm, 15mm, 19mm, etc.) and thicknesses. It is available in rolls for manual application and in coils for automatic machines. Coreless coils and wound reels are typical for high-volume packaging lines. The choice of width and thickness depends on load weight, package dimensions, and equipment compatibility.

Sealing and joint methods

• Heat/Frictio n weld (for PET): Machine welds melt the strap ends together, creating a clean, strong joint—ideal for PET.
• Crimp seals (metal): Metal seals are applied with a sealer tool and compressed around overlapping strap ends—common for both PP and PET.
• Plastic buckles/joints: Reusable plastic buckles are used for manual bundling and temporary holds.
• Friction welds (manual or machine): Friction tools can fuse straps without metal hardware for a tidy finish.

Typical applications

Plastic strapping is used in industries ranging from e-commerce fulfillment to construction. Typical uses include pallet unitizing, carton bundling, timber banding, brick and block packs, and securing coils or rolls. PP is often chosen for light carton closure and low-cost bundling. PET is selected for heavy pallet loads, international shipping where long-term tension retention is needed, and where it may replace steel strapping for safety and handling advantages.

Advantages over alternatives

• Compared with steel: Plastic strapping (especially PET) can match many steel applications while being safer to handle (no sharp edges), lighter, and corrosion-resistant.
• Compared with cord strapping: PET offers higher tensile strength in a thinner profile and lends itself to machine application.
• Handling and safety: Plastic straps reduce risk of cuts and rust-related stains on packaged goods.

Practical beginner tips

• Match strap strength to load weight and package design—over- or under-sizing can cause failures or waste.
• Use edge protectors on fragile or soft-cornered loads to prevent strap cutting or deformation.
• If you need long-term tension retention (warehouse storage, export), prefer PET over PP.
• Train staff on safe tensioning and sealing methods—incorrect use can damage products or cause injury.
• Store strapping away from direct sunlight and extreme heat to prevent degradation, especially for PP.

Example scenarios

• Small e-commerce business: Use 12mm PP strapping for carton closure—cost-effective and adequate.
• Manufacturer exporting pallets overseas: Use 19mm PET with heat-welded joints for stable long-haul retention.
• Construction materials yard: Use wider PET or heavy-duty PP with seals for bundling timber or blocks.

Conclusion



For beginners, think of PP as the economical, elastic choice for light, temporary jobs, and PET as the stronger, low-elongation choice for heavy loads and longer-term stability. Both have important roles in packaging and logistics; the right choice depends on load, duration, environment, and cost considerations.