CHEMISTRY OF MATERIALS
Learning outcomes of the course unit
To provide the basic concepts of science and technology of the main packaging materials.
The knowledge of basic elements of chemistry and physics is not formally compulsory, but is suggested.
Course contents summary
Primary and secondary packages and shippers. Chemical and physical properties. Introduction to mechanical properties. Diffusive properties. Migration.
Glass: Definition Glass transition temperature. Structure. Oxides classification. Relationship composition-properties - Chemical-physical and mechanical properties – Viscosity. Thermal dilatation. Industrial production of glass - Main tests on glass – Stress in glasses – Tempered glasses– Glass as a primary package: technical and commercial aspects – Environmental impact - Crystallizzation of glass: glassceramics.
Wood: Main features - Structure – Composition - Chemical-physical and mechanical properties – Processing methods and Semifinished products. HT and MB treatments. Defects. Composition and chemical reactions of main wood constituents. Container typologies. Cork.
Paper: Definition and origins. Raw materials (pulps) - Production process - Main tests on Paper – Packaging papers: papers for Corrugated board (facings and fluted media) and Papers for packaging and packing for applications other than corrugated board - Paper packages. Environmental impact .
Board: Different kinds of fibreboard - Main tests on board – Board Packages – Factors to consider when designing a board package.
Corrugated board: Definition - Facings – Flutes – Adhesives – Identification of a Corrugated board - Grammage – Industrial production and transformation of corrugated board – Defects and tests - Corrugated board packages – How product properties affect the choice of a corrugated board package - McKee Formula - Mechanical resistance – Comparison of Corrugated board with other materials - Environmental impact of paper-based materials.
Metals: Metals and alloys - Iron extraction. Cast iron. Fe-C alloys – Fe-C Diagram - Steels: production, processing, mechanical properties, thermal treatments, compositions.
Tin plate: Fabrication and applications – Interactions container-product – Protective coatings – Tin Free Steel and Low Tin Steel. Aluminum: properties, main alloys. Notions about the corrosion of metals. Metal packages in coated steel and aluminum: 3–piece and 2-piece cans, aerosols - Production processes and properties. Notions about other types of metal containers. Coatings for metals. Comparison among metal materials performances. Recycling. Flexible packaging laminates: Definition and preparation methods - Criteria for the choice of laminate components and examples.
o Plastic: Production and manufacturing. Manufacturing methods identification. Packaging applications. PE, PS, PP, PET, PVC, PVDC, EVOH, PA, Ionomers and copolymers. Addictives. Identification symbols. Natural fibers: introduction to juta and cotton bags. Adhesives: Adhesion and cohesion. Common classes of packaging adhesives. Criteria for the choice of adhesives. Lacks of bonding.
Duplicated lecture notes provided by the lecturer.
VERIANO VIDRICH “Il legno e i suoi impieghi chimici”, EDAGRICOLE;
WALTER SOROKA “Packaging Technology”, ISTITUTO ITALIANO IMBALLAGGIO;
Monografia sul Cartone Ondulato, GIFCO;
LUCIANO PIERGIOVANNI: Dispense del corso “Tecnologie del Condizionamento dei Prodotti Agro-Alimentari”, Università di Milano.
Several textbooks available as analysis and reference books.