• TestingCrude oil and petroleum productsPolyolefins (polypropylene and polyethylene)

    Polyolefins (polypropylene and polyethylene)

    The polyolefins are homopolymers and copolymers of hydrocarbons containing one double bond in their molecules. The most used plastics not only among the polyolefins but also others are polyethylene and polypropylenes. Usually, they are delivered in form of granules. Doped and non-doped types are under manufacture, containing different additives that assure a protection during processing and prolongate the service life and modifies the performance.

    At the test labs, we focus on the evaluation of the natural (without addition of artificial pigments) low-density polyethylene and polypropylene or its copolymers, respectively (thermoplastics, impact-resistant and random copolymers).

    The low-density polyethylene (hereinafter “LD-PE”) is produced by the high-pressure polymerization of ethylene at the autoclave or tubular reactor in presence of peroxide initiators or modifiers. The particular LD-PE types are qualitatively different by basic parameters, e.g. density, molecular mass and processing characteristics.

    The polypropylene (hereinafter “PP”) are usually produced using the Ziegler-Natta catalysts by a polymerization in the fluidized bed. The properties of the produced PP depend on the length of created chains, which is the molecular mass and its distribution, molecular and hyper-molecular structure, i.e. on the isotactical structures, the cristallinity degree and, as for copolymers, on the ethylene content, in particular. These structural characteristics are given through the applied polymerization technology and the type of catalytic complex. The PP may be produced using the controlled rheology, or as the reactor type without peroxide addition.

    Typical tests for polyolefins

    Determination of mass index of the LD-PE and PP smelt flow
    Determination of visual color of the LD-PE granulate
    Quality evaluation of the LD-PE or PP testing foil (visually and using device)
    Determination of dynamic friction coefficient
    on sloped and horizontal plane
    Determination of corrosion under tension at the environment of tensioactive compounds (ESCR F50)
    Vicat softening temperature determination
    Determination of smelt growth coefficient
    Evaluation of mechanical properties of foil types LD-PE on foil
    Evaluation of mechanical properties of LD-PE injection bodies
    Impact resistance of the foil against the falling pestle
    Determination of the LD-PE foil contractibility
    Weld strength
    Double bond determination in LD-PE
    Transmittance evaluation of the foil in UV light
    Determination of CO index from LD-PE
    Determination of impurities content and appearance properties of the LD-PE or PP granulate
    Determination of creep properties of the LD-PE foil
    Determination of bulk density of LD-PE granulate
    Determination of yellowness and whiteness index for granulate, plate or fiber
    Determination of the soluble portion in xylene from PP
    Homogenization of PP powder
    Determination of ethylene content in the ethylene-polypropylene copolymer
    Cup test of the polypropylene powder flow
    Determination of Rockwell hardness
    Bulk density determination of PP granulate and powder
    Filtrability of polypropylene
    Determination of the polypropylene cracking efficiency
    Evaluation of the modulus in tension and bending of PP injection bodies
    Evaluation of mechanical properties of PP injection bodies
    Determination of PP powder particles size distribution
    Izod impact strength test
    Visual yellowness determination of PP granulate
    HDT test
    Determination of metals and additives content in the polymer. X-ray method
    Blooming determination from the injection bodies
    Gas fading test
    Charpy impact test of polypropylene
    Determination of long-term thermal-oxidative stability of PP and PP-copolymers in oven
    Determination of optical properties from foil and injection bodies
    Determination of ash content (non-combustible portion) from polyethylene (LD-PE) and from polypropylene (PP)
    Density determination of LD-PE and PP
    Shore Durometer Hardness Testing (indentation method)
    Evaluation of rheological properties of PE and PP - flow curves at the Rheometer 5000 Ceast
    Determination of melting point and crystallization temperature of polyolefins and additives – DSC method
    The induction period of oxidation of polyolefins by DSC method
    The initial temperature of oxidation of polyolefins by DSC method
    Determination of decomposition temperature and mass loss for polyolefins and additives – TGA method
    Thermal oxidation stability of polymers by a repeated re-granulation using the equipment Collin E 30 P
    Material identification using ATR on the FTIR spectrophotometer
    Shrinking of the injection bodies
    Gloss assessment of foil or injection bodies
    Sensory evaluation of odor features
    Preparation of a test sample on a foil line SAMAFOR and the foil application test
    Preparation of the test bodies from PP and PE by pressing
    Mixing of polypropylene powder samples
    Granulation – preparation of laboratory samples of PP
    Preparation of test bodies at the injection molding machine Batenfeld
    Preparation of fibers on the laboratory spinning line FDY/)BCF Spintester made by Fourné Polymertechnik
    Homogenization of LD-PE material by calendering
    Determination of dust particles in granulate by the wet method on Pelletron device