18/05/2026
How to Improve Puncture Resistance in Stretch Film
In stretch film production, one common problem is that the film breaks easily when wrapping sharp-edged cartons, irregular pallets or heavy loads.
Many people think the solution is simply to increase film thickness. But in most cases, poor puncture resistance is not only a thickness problem. It is usually related to resin selection, formulation balance, layer structure and processing control.
A good stretch film should not only stretch well. It should also recover, hold the load and resist puncture under real packaging conditions.
# # Why does stretch film have poor toughness?
There are several common reasons.
First, the formulation may rely too much on general-purpose LLDPE, such as conventional C4 LLDPE or 7042 grades. These materials are cost-effective and suitable for ordinary hand stretch film, but they may not be enough for downgauging, high pre-stretch ratio or machine stretch film.
Second, the film structure may not be balanced. If the core layer does not have enough high-performance polyethylene, the film may lose toughness after stretching. If the formulation is too stiff, the film may split under puncture. If it is too soft, the film may lose load retention.
Third, excessive recycled material, filler, off-grade resin or poor dispersion can create weak points in the film. Gels, fish eyes, die lines and uneven thickness can all reduce puncture resistance.
Fourth, processing conditions are also important. Over-stretching, unstable extrusion temperature, poor cooling and uneven gauge control can make the film easier to break.
# # How to improve puncture resistance?
The first step is to use the right LLDPE base resin.
For ordinary stretch film, LLDPE such as SABIC 218W / 218WJ / 118WJ / 118NJ and DFDA-7042 from Zhenhai Petrochemical, PetroChina Jilin and Wanhua Chemical can be used as cost-effective base materials.
These grades are suitable for general hand wrap film, blown film, cast film and packaging film applications.
However, if the customer wants better puncture resistance, thinner film or higher machine performance, conventional LLDPE alone is usually not enough.
The second step is to upgrade the core layer with metallocene LLDPE.
Metallocene LLDPE can provide better tensile strength, impact resistance, puncture resistance, film uniformity and downgauging potential. It is especially useful for thin-gauge stretch film, machine stretch film and high-performance pallet wrap.
The third step is to use POE, POP or elastomer modifiers properly.
POE and POP are not just “soft materials”. In stretch film formulations, they can improve flexibility, elongation, elastic recovery, impact resistance, low-temperature toughness and puncture resistance.
But the dosage must be controlled carefully. Too much elastomer may reduce stiffness, holding force or roll handling performance.
For high-performance stretch film, the formulation is usually not based on one single resin. A better solution is often:
LLDPE as the cost-effective base resin.
mLLDPE as the main strength and puncture-resistance upgrade.
POE / POP as the toughness, flexibility and impact modifier.
Cling modifier as the adhesion solution.
Good processing control as the final guarantee.
# # Our resin solutions
For customers producing stretch film, cling film and flexible packaging film, we can provide different resin solutions according to your film structure, thickness, process and target performance.
For metallocene LLDPE, we can supply Mitsui Chemicals EVOLUE™ SP1520, which is suitable for improving film toughness, tensile strength, puncture resistance and downgauging performance.
For elastomer and plastomer modification, we can supply SK POP 021, Dushanzi 0588 POE, ExxonMobil 6102 performance polymer and Wanhua WANSUPER® 5007 POE.
These materials can help improve flexibility, elongation, elastic recovery, impact strength and puncture resistance. They are especially suitable for stretch film, machine wrap film, cling film and flexible packaging film applications.
Cost control is also becoming very important for film manufacturers. Dow and ExxonMobil POE materials offer excellent performance, but for many cost-sensitive customers, the price can be too high.
In this case, China-made Wanhua WANSUPER® 5007 POE can be a practical alternative option. Depending on the market price and final formulation, it may help customers reduce POE material cost by around USD 200/MT while maintaining a good balance of toughness, flexibility and impact modification performance.
There is no single resin that fits every stretch film formulation. The best solution depends on the customer’s process, film thickness, pre-stretch ratio, cling requirement, load type and target cost.
If you are producing stretch film, cling film or flexible packaging film and want to improve puncture resistance or reduce formulation cost, we can help recommend suitable LLDPE, mLLDPE, POP and POE grades for your application.
