摘要:
There is provided a laminated sheet comprising: (i) a foamed sheet containing a polypropylene resin; and (ii) a non-woven fabric, wherein the foamed sheet has an expansion ratio, &khgr;, of from about 2 to 10, a cell diameter of not more than about 300 &mgr;m, and a thickness, h (cm), satisfying the following formula (1), (100/E(1−(1−1/&khgr;)⅔))⅓≦h≦2 (1) wherein E (kgf/cm2) is a modulus of elasticity in bending of the resin which is to be a constituent of the foamed sheet and is not yet foamed.
摘要:
The invention provides, as a method for producing a multi-layer foamed sheet whose scale-like appearance has been improved by means of a multi-layer circular die coextrusion method, a method for producing a multi-layer foamed sheet having foam layers and non-foam layers by a multi-layer circular die coextrusion method which is a method for producing a multi-layer foamed sheet wherein the shear stress at the interface of each layer is 5000 Pa or higher and not higher than 50000 Pa, a method for producing a multi-layer foamed sheet wherein the resin of said non-foam layer is a linear propylenic resin having a melt flow rate of 5 to 30 g/10 minutes, and a method for producing a multi-layer foamed sheet wherein the resin of said foam layer is a propylenic resin whose melt tension (MT) at 190° C. and melt flow rate (MFR) at 230° C. satisfy the following equation A: MT≧7.52×MFR (−0.576) [Equation A]
摘要:
The present invention provides a process for producing uncrosslinked polypropylene-based resin foam sheets which is characterized by using an extrusion foaming apparatus having a gear pump which is interposed between the extruder and the die and which is linked by means of adapters, wherein the pressure (Pg) at the inlet of the gear pump is within the range specified by the following formula (Formula 1) and the extruder is controlled so that the value of Pg is constant. Formula 1 Pc≦Pg(atm)≦Pc+90 Pc=(&khgr;−1)/H &khgr;: theoretical expansion ratio when the foaming agent added is 100% held H: coefficient of solubility of the foaming gas in the resin at the resin temperature in the gear pump inlet (cm3(STP)/cm3·atm) and the like. The present invention makes it possible to produce uncrosslinked polypropylene-based resin foam sheets having fine foam cells and good appearance and being excellent in productivity and extrusion stability as well as in productivity improving effect in the production of high-expansion thin sheets with reducing wavy or corrugated defects at ends of sheets.
摘要:
A polypropylene is disclosed which is a linear polypropylene having a ratio of a Z-average molecular weight Mz to a weight-average molecular weight Mw, Mz/Mw, determined by gel permeation chromatography of 4.1 or more, a swell ratio of from 1.4 to 1.8, and an activation energy of flow of from 48 to 105 kJ/(mol·K).
摘要:
The present invention relates to a polypropylene resin composition containing about 90 to 60 parts by weight of a polypropylene block copolymer (A); and about 10 to 40 parts by weight of a polyethylene resin (B), wherein the polypropylene block copolymer is a polypropylene block copolymer which contains about 99 to 90% by weight of a crystalline polypropylene (a) and about 1 to 10% by weight of an amorphous ethylene-.alpha.-olefin copolymer (b) and has a melt flow rate (MFR) of about 2 to 15 g/10 minutes, and a die swell ratio, measured by a capillary rheometer, of at least 1.7. Foamed materials containing a fine and uniform foam are obtainable from this composition.
摘要:
There are disclosed: (1) a container comprising a foamed olefin resin, wherein weight W (g) and content volume V (ml) of the container satisfy the following expression (1): W(g)/V(ml)≦0.055 (1), and (2) a process for producing the container by a blow molding method.