Abstract: A method for analyzing semifinished products including reinforcing fibers having an essentially unidirectional orientation and a thermoplastic resin, including a first and a second test for measuring the thickness of a stack of semifinished products over time during the compression thereof and for determining the equivalent homogeneous viscosity of the stack; determining the total thickness reduction of the stack of semifinished products during the first test; determining the ratio of the equivalent homogeneous viscosity of the stack from the second test to the equivalent homogeneous viscosity of the stack from the first test; and determining the ratio of the thickness of the stack from the first test after a reference time starting from the moment of the onset of melting of the stack of semifinished products, to the thickness of the stack from the first test at the moment of the onset of melting of the stack of semifinished products.

Abstract: A process including: the provision of a semicrystalline or crystallizable composition, having a glass transition temperature Tg, including at least one polyaryletherketone; the provision of a compression forming means including: a mold, the mold having at least one cavity; the preparation of the composition in the molten state in said at least one cavity, the mold having a temperature T0 at the end of the preparation stage; the compression and the cooling of the composition in the molten state, the mold being cooled from the temperature T0 down to a final temperature Tf of less than or equal to (Tg+30)° C., to form a compression-formed article; and the removal of the compression-formed article from the mold; in which the composition has a melting point strictly of less than 340° C.

Abstract: A method for analyzing semifinished products including reinforcing fibers having an essentially unidirectional orientation and a thermoplastic resin, including a first and a second test for measuring the thickness of a stack of semifinished products over time during the compression thereof and for determining the equivalent homogeneous viscosity of the stack; determining the total thickness reduction of the stack of semifinished products during the first test; determining the ratio of the equivalent homogeneous viscosity of the stack from the second test to the equivalent homogeneous viscosity of the stack from the first test; and determining the ratio of the thickness of the stack from the first test after a reference time starting from the moment of the onset of melting of the stack of semifinished products, to the thickness of the stack from the first test at the moment of the onset of melting of the stack of semifinished products.

Abstract: A process including: the provision of a semicrystalline or crystallizable composition, having a glass transition temperature Tg, including at least one polyaryletherketone; the provision of a compression forming means including: a mold, the mold having at least one cavity; the preparation of the composition in the molten state in said at least one cavity, the mold having a temperature T0 at the end of the preparation stage; the compression and the cooling of the composition in the molten state, the mold being cooled from the temperature T0 down to a final temperature Tfof less than or equal to (Tg+30)° C., to form a compression-formed article; and the removal of the compression-formed article from the mold; in which the composition has a melting point strictly of less than 340° C.

Abstract: The present invention relates to a coextrusion binder useful for petrol tanks of HDPE/binder/EVOH or PA/binder/HDPE structure.

Abstract: The present invention relates to a coextrusion binder comprising: 5 to 30 parts of a polymer (A), itself comprising a blend of a polyethylene (A1) of relative density between 0.935 and 0.980 and of a polymer (A2) chosen from elastomers, very low-density polyethylenes and ethylene copolymers, the (A1)+(A2) blend being cografted with an unsaturated carboxylic acid; 95 to 70 parts of a polyethylene (B) of relative density between 0.930 and 0.950; the blend of (A) and (B) being such that: its relative density is between 0.930 and 0.950, the content of grafted unsaturated carboxylic acid is between 30 and 10,000 ppm, the MFI (melt flow index) measured according to ASTM D 1238 at 190° C./21.6 kg is between 5 and 100. This binder is particularly useful for petrol tanks of structure: HDPE/binder/EVOH or PA/binder/HDPE.