New opportunities for PE film converters: Borclear™ and Borsoft™ polypropylene

Borealis has developed a range of polypropylene (PP) blown film materials designed for production on conventional blown-film machinery traditionally used for polyethylene.

The new polypropylene materials, including Borclear and Borsoft, take advantage of molecular engineering to overcome previous material shortcomings for blown-film production. Borealis innovation has overcome the attributes of conventional PPs by increasing melt strength, developing molecular structures to prevent splitting, and greatly enhancing cooling and optical properties. The new materials are fully capable of production on equipment designed for conventional PE films.

In addition, the PP blown-film materials provide a range of properties and possibilities for film appearance, mechanical behaviour, and potential for use in new applications, including:

• stiff packaging film for textiles or foodstuffs with excellent gloss and heat sealing,

• films for hygiene uses (diapers, incontinence products) with good mechanical properties,

• stand-up food pouches with balanced toughness and stiffness,

• labelling film with outstanding planarity and stiffness (consistency of section for ease of cutting) and

• packaging films with water and gas barrier properties combined with good optical properties.

“Borclear and Borsoft PP-based materials offer blown-film converters a unique chance to enter new applications and markets with their current machinery," says Anton Wolfsberger, Marketing Manager Film & Fibre. “Converters now have new options to improve profitability by adding value to their current customers and offering something unique to attract new customers.”

The newly developed Borclear RB707CF (MFI = 1,8g/10 min) delivers unique optical properties, which have never been achieved before in conventional blown film technology . These incredible optics are impressing the film industry and packaging experts due to its perfectly adapted polymer structure and defined crystallization behaviour. Traditional film converters now have the opportunity to expand their product portfolio and their market applications with this new development in the area of food packaging films and other transparent applications.

Additionally, the Borsoft SA233CF is mainly used in coextrusion or blends to upgrade the impact and tear properties of films – in combination with its good sealing behaviour and temperature resistance. A typical use for this grade is in the hygienic film area to enable down gauging of existing PE film structures in the range of 20 to 30 %.

The range of properties available stem from the molecular design available to PPs, including:

• homopolymers - known for highest stiffness, tensile strength and water barrier strength,

• random copolymers - excellent heat sealing and excellent optical properties, like the new Borclear RB707CF grade,

• heterophasic copolymers, like BHC5012 or BA110CF - matt surface, high toughness, wide temperature range and

• the newly-developed random heterophasic copolymers – like Borsoft SA233CF; outstanding toughness and good softness, excellent and heat-sealing capabilities and stress-whitening resistance.