Methods of making continuous length reinforced plastic articles

• US 3,993,726 A
• Filed: 01/16/1974
• Issued: 11/23/1976
• Est. Priority Date: 01/16/1974
• Status: Expired due to Term

• Current Assignee: Hercules Incorporated (Ashland Global Holdings, Inc.)
• Original Assignee: Hercules Incorporated (Ashland Global Holdings, Inc.)
• Inventors: Moyer, Richard L.
• Primary Examiner(s): Woo, Jay H.
• Application Number:
  US05/433,983
• Time in Patent Office: 1,042 Days
• Field of Search: 264/174, 264/209, 264/210 F, 264/178, 264/151, 264/323, 264/299, 264/280, 161/177, 161/178, 156/180
• US Class Current: 264/171.12
• CPC Class Codes: B29B 15/122 with a matrix in liquid form, e.g. as melt, solution or latex
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/06 Rod-shaped
• CPC Class Codes: B29C 48/09 Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
• CPC Class Codes: B29C 48/156 Coating two or more articles simultaneously
• CPC Class Codes: B29C 48/21 the layers being joined at their surfaces
• CPC Class Codes: B29C 48/90 with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
• CPC Class Codes: B29C 48/908 characterised by calibrator surface, e.g. structure or holes for lubrication, cooling or venting
• CPC Class Codes: B29C 48/911 Cooling
• CPC Class Codes: B29C 48/919 using a bath, e.g. extruding into an open bath to coagulate or cool the material
• CPC Class Codes: B29C 70/521 and impregnating the reinforcement before the die
• CPC Class Codes: B29K 2105/14 oriented
• CPC Class Codes: B29K 2105/251 Particles, powder or granules expandable particles B29K2105/046
• CPC Class Codes: D01D 11/06 Coating with spinning solutions or melts

Abstract

Methods of making continuous length articles of reinforced plastic material includes passing rovings of temperature resistant material through a crosshead extruder to impregnate the rovings with a thermoplastic polymer under high pressure. The impregnated rovings are pulled from the extruder through a die and are cooled and shaped into a void free article having a desired cross-sectional shape.

Claims

1. A method of making reinforced plastic articles comprising:

advancing one or more continuous length rovings of temperature resistant material into a crosshead extruder die;

forcing molten polymer into said die under relatively high pressure to impregnate said rovings;

cross-section;

continuously extruding and pulling said impregnated rovings through one or more exit orifices of said die to consolidate and shape said impregnated rovings into an article having a substantially uniform cross-section;

at least partially cooling said article to harden the outer surface thereof; and

compressing said article during cooling to remove voids therein and provide a uniform cross-section wherein said rovings comprise between about 30% to 90% by weight of said article.

2. A method of making reinforced plastic articles as set forth in claim 1 including cooling the article during the compressing step to a temperature below the crystallization point of the polymer.

3. A method of making reinforced plastic articles as set forth in claim 1 wherein baffles are provided in said die to separate the rovings to increase impregnation thereof.

4. A method of making reinforced plastic articles as set forth in claim 1 wherein said rovings comprise between about 30-90% by weight of said article.

5. A method of making reinforced plastic articles as set forth in claim 1 wherein said rovings are advanced into and through said crosshead extruder die in a flat planar array.

6. A method of making reinforced plastic articles as set forth in claim 5 wherein the flat article formed is separated into a plurality of tapes.

7. A method of making reinforced plastic articles as set forth in claim 1 wherein said rovings are advanced into said crosshead extruder die in a tubular array and are formed about a mandrel into a pipe.