Developments in Oriented Polypropylene for Durability

Recyclable packaging film with improved tear resistance for easier opening compared to traditional multi-layer films. The film has a biaxially oriented polypropylene (BOPP) layer between 1-10 microns thick sandwiched between a supporting polyethylene layer and a sealing polyethylene layer. The BOPP layer provides dimensional stability and the polyethylene layers allow recyclability. The thin BOPP layer enables controlled tearing and smooth opening without needing complex operations like perforation or scoring. The thin BOPP layer also avoids detrimental resins.

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Barrier laminate for packaging applications with improved gas barrier properties and tear resistance compared to conventional laminates using polyester films. The laminate has a stretched polypropylene substrate with an evaporated film, followed by a sealant layer. The stretched polypropylene substrate improves tear resistance. The evaporated film, made of an inorganic oxide, provides gas barrier. The laminate after heat treatment has low thermal shrinkage. This structure allows high gas barrier without needing an adhesive layer between the substrate and sealant. The stretched polypropylene substrate also enables recycling the laminate as a single material.

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Food contact materials (FCMs) with improved properties for food packaging applications. The FCMs contain a combination of polypropylene resins with different molecular weights, along with a small amount of hydrocarbon resin. This composition provides high stiffness, snappability, barrier properties, thermoformability, and optical properties for food packaging while maintaining clarity. The FCMs can have properties like tensile modulus >2.5 GPa, water vapor transmission rate <0.005 g/100 in2/48 hr, and oxygen transmission rate <0.07 cc/pkg/24 hr.

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Flexible container carrier for packaging multiple containers with improved elastic recovery after container insertion. The carrier has a flexible sheet with primary apertures for receiving container parts. The sheet is made with a specific polymer composition containing a high percentage of hexene, like 11-24%, in addition to propylene and ethylene. This composition provides better elastic recovery after stretching during container insertion compared to conventional polyolefin blends.

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Expandable packaging material that provides structural strength and customization options for shipping enclosures. The packaging material has two layers, one that expands in a direction and the other that expands in a perpendicular direction when the first layer is pulled. This expansion creates pockets and increases thickness for structural support. The expandable layers allow customization by expanding to fit item sizes.

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Evaluating stretch wrap packaging material quality by testing it under controlled tension conditions to determine specific containment force. A take-up drum with a force sensor is used to wrap the material around it. The controlled stretch is varied to find the tension where flaws propagate. This allows comparing packaging material qualities and optimizing wrapping machine settings for specific materials.

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High-performance multilayer film for packaging that provides improved properties like peel strength and heat-sealing without delamination or tearing. The film structure involves sandwiching layers with different stretching ratios between transition layers. These transition layers have similar properties to bridge the layers and reduce internal stress. The transition layers have a bonding layer with adjusted solubility and cohesive energy density to match the adjacent layers. This gradual transition prevents interlayer peeling and tearing during stretching.

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Process for making multilayer polymeric shrink pouches with strong shrinkage in the transverse direction and minimal shrinkage in the longitudinal direction. The process involves three stages: (1) making a flattened blown film with multiple layers, (2) stretch orienting the film longitudinally while restraining transverse dimensions, and (3) forming pouches using this stretch-oriented film. This creates pouches that shrink strongly in the transverse direction when heated, but have little longitudinal shrinkage.

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Recyclable packaging with a multi-layer structure that allows for easy separation of the layers to enable recycling. The packaging has an inner wall with three layers: a thin biaxially oriented polypropylene (BOPP) layer, a metallized cast polypropylene (CPP) layer, and a thicker CPP layer. The outermost BOPP layer is exposed. The inner layers can be separated from each other by peeling apart the BOPP layer without adhesion between the inner layers. This allows easy recycling of each layer individually.

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Packaging tissue products to allow simpler control of the components affected by the drawing of the plastic film. The packaging method includes a step of drawing the film along an operating path.

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Evaluating stretch wrap packaging material quality to determine its performance and suitability for wrapping loads. The evaluation involves subjecting the packaging material to controlled stretching conditions and measuring properties like containment force, flaw behavior, and hole propagation. This allows comparing different packaging materials and determining optimal wrapping settings for specific materials. The evaluation can be done using a specialized testing apparatus that applies controlled stretch to the packaging material before wrapping it around a take-up drum to measure containment force. Simulated flaws can also be introduced to study how they behave under stretch.

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A thin, lightweight, high-strength, reinforced plastic film for flexible packaging that provides enhanced mechanical properties like tear resistance and tensile strength while keeping the weight low. The film has a base film made of a stretchable polyolefin material with extruded fibers placed on at least one surface. The fibers protrude above the base film surface. When the fibers are extruded onto the base film, they crystallize and bond to the base material to create a strong interfacial mixing domain. This prevents tear propagation better than laminating a separate strip since it has sufficient interfacial mixing area to absorb energy.

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A device and method for blowing and stretching thermal shrinkage packaging films that allows homogeneous stretching in both the longitudinal and lateral directions. The device has multiple stages with press rollers and blow-expansion mechanisms. The first stage blows up the film with a lateral opening ratio of 1:1. The middle stage flattens and stretches longitudinally. The rear stage further stretches. Roller speeds differ between stages. This creates homogeneous stress in both directions. The method involves blowing up the film, longitudinal flattening, further stretching, and shaping.

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A packaging film for single-use hygiene products that has excellent mechanical properties while being thin. The film is made from a multilayer polymeric film with specific properties. It has an elongation of up to 1% under a tensile force of 3 N per 25 mm width, and a thickness of ≤18 μm, preferably ≤12 μm. The film has a monoaxial orientation in machine direction of at least 1:2, preferably 1:3, and an orientation ratio in machine and transverse directions of 1:2 to 1:3.5. The film has a sealable layer on both sides.

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Heat-sealable, peelable packaging film for puncture-prone products like crackers. The film has a core layer made of puncture-resistant biaxially oriented polypropylene (BOPP) containing a propylene-ethylene copolymer. An intermediate peelable layer with a peeling agent is sandwiched between the core and an interior skin layer. The core layer's puncture resistance is enhanced by adding an elastomeric propylene-ethylene copolymer to the core layer composition. This allows the film to be heat-sealed, peeled easily, and have improved puncture resistance compared to pure BOPP.

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Compression packaging for protecting compressible items like food products during shipping and storage. The packaging is made of a monoaxially drawn film with thicker edges that cover the item's ends. This provides enhanced protection at the vulnerable end faces compared to the thinner main body. The thicker edges prevent damage to the item when stacked. The monoaxial drawing process increases film strength and reduces thickness.

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A multilayer biaxially-oriented polypropylene (BOPP) cigarette packaging film with improved properties for moisture protection, slip, toughness, lightweighting, and anti-counterfeiting compared to conventional BOPP films. The film has multiple layers with specific mass percentages: an upper BOPP surface layer, two antibacterial BOPP layers sandwiched between a stiffening BOPP layer and the lower BOPP surface layer. The film is manufactured by co-extrusion and biaxial orientation. The multiple layers provide better moisture barrier, slip, toughness, and anti-blocking properties compared to single-layer BOPP films. The antibacterial layers inhibit microbial growth. The layered structure enables lightweighting compared to thick single-layer BOPP films. The film also has lower carbon footprint compared to thicker BOPP films.

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Automating the packaging of lettuce heads in the field to improve efficiency and reduce costs compared to manual packaging. The automated packaging involves using a stretchy wrap with an elastic portion around the opening. The wrap is stretched wide enough to place the lettuce head inside. Once the head is inside, the stretched elastomeric portion is released, and the relaxed elastomeric portion holds the wrap around the head without taping. This eliminates the need for a separate packer to twist and tape the head, as the elastic wrap provides a secure hold.

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Tube packaging film with improved barrier properties for packaging products like toothpaste and foodstuffs. The film has at least one plastics layer and an oriented barrier layer. The oriented barrier layer has molecular directional orientation, achieved through stretching or orientation, which provides a stronger barrier to oxygen compared to a non-oriented barrier layer of the same thickness. The oriented barrier layer improves the barrier properties of the tube packaging compared to using a non-oriented barrier layer.

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Hermetically sealable packaging films for food preservation that combine high oxygen barrier properties with the ability to form hermetic seals. The films are oriented polymer films like biaxially oriented polypropylene (BOPP) or biaxially oriented polyethylene terephthalate (boPET) that can provide high oxygen barrier without relying on thick inner sealant layers. The films are stretched over 40 times in both directions for orientation. To form hermetic seals, impulse or ultrasonic sealing methods are used instead of traditional heated bar sealing. These methods provide rapid heating and cooling cycles with continuous pressure to prevent shrinkage and deformation.

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