Polymer Films

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The Industrial Materials Institute (IMI) of the National Research Council of Canada (NRC) is currently carrying research in the area of polymer films. The approach is to study films process-structure-performance relationships for either multilayer or monolayer films using the blown film, cast film and biax (tenter) film processes.

The objectives are to:

• relate the process parameters to the structure (morphology and orientation) developed in films;
• develop models and relations between structure and performance of films (mechanical, shrinkage, tear, barrier etc.);
• develop techniques for monitoring films processes (thickness, crystallinity, orientation, etc.);
• develop models and simulation tools for the optimization of films processes

Film process-structure-performance relationships

Film manufacturing processes are already well established, the concern is more on their optimization through material's characterization, feasibility studies, films and formulations for specific application, process monitoring and pilot plant testing.

Efforts are underway to develop process-structure relationships on one hand and structure-performance on the other and to monitor the structure of films that can be obtained from different processes and process conditions.

5 extruder – 5 layer coextrusion film blowing line 100 mm diameter die

Performance is analyzed and related to the microstructure using:

• mechanical tests (modulus, strength and elongation at yield and rupture);

• impact tests (Izod, Charpy, falling weight);

• permeability measurements for different gases and hydrocarbons;

• tear tests;

• haze and gloss tests;

• shrinkage tests.

Different types of polymers, such as polyethylene, polypropylene, polyesters, nylons and many others are studied.

Film structure and orientation characterization

As the important factors for the enhancement of the properties are the molecular orientation induced in the material upon deformation and the morphology, it is important to determine the microstructure and quantify the degree of orientation. Orientation measurement techniques are being used and developed for characterization and process control purposes. These include:

• birefringence (biaxial, off-line and on-line);

• infrared spectroscopy (biaxial);

• X-ray scattering (WAXD and SAXS).

Determination of microstructure is completed using:

• thermal analysis (DSC and MDSC);

• scanning and transmission electron microscopy0;

• atomic force microscopy.

Film processes simulation and optimization

Focus is directed here to the integration of the models and relations developed above with existing films extrusion software such that performance of the final films can be predicted.

Facilities

The following equipment, specific to film processes and characterization, are available at IMI.

Collaboration with Industries

Companies interested in polymer films are encouraged to participate in the research activities being undertaken at IMI. The work can be carried out in the form of:

• joint project with an integrated approach which could involve other expertise available at IMI in modelling and control;

• feasibility study for process or product development;

• technical support using specific or unique expertise and/or equipment.

Information

Through R&D projects and pre-competitive research, IMI works with companies and helps them in a progressive technology transfer process. To learn more about these and other technologies, you are invited to contact IMI representatives.

Lucie Robitaille, Ph.D. Group Leader Functional Polymer Systems Tel.: 450-641-5032 Fax: 450-641-5105 E-mail: Lucie.Robitaille@cnrc-nrc.gc.ca
Alexandre Paris, Eng. Business Development Officer Advanced Materials Design Tel.: 450-641-7524 Fax: 450-641-5105 E-mail: Alexandre.Paris@cnrc-nrc.gc.ca

Related Information

Institutes:

• NRC Industrial Materials Institute