| 摘要 |
A PROCESS FOR THE MANUFACTURE OF THIN-WALLED ARTICLES COMPRISING THE STEPS OF: 1) SELECTING A POLYMER BLEND HAVING AN ESCR OF GREATER THAN 10 HOURS; i) A PLURALITY (PREFERABLY 6 OR MORE) STRIPS OF THE POLYMER BLEND INCORPORATING ANY POST MOULDING TREATMENT INTENDED FOR THE FINAL ARTICLE HAVING THE CROSS-SECTIONAL DIMENSIONS OF 0.65 MM IN THICKNESS AND 10 MM IN WIDTH ARE INJECTION MOULDED UNDER HIGH SHEAR, LONG FLOW LENGTH CONDITIONS, SIMILAR TO THOSE INTENDED FOR USE IN THE MANUFACTURE OF THE FLEXIBLE THIN-WALLED ARTICLE.; ii) THE STRIPS ARE BENT BACK UPON THEMSELVES AND STAPLED 3 MM FROM THE BEND; iii) THE BENT STRIPS ARE IMMERSED IN A SOLUTION OF A STRESS CRACK AGENT AND HELD AT A TEMPERATURE OF 50°C; IV) THE STRIPS ARE OBSERVED FOR SIGNS OF CRACKING, ANY SIGNS OF CRACKING ARE REGARDED AS A FAILURE; AND V) THE TIME TO FAILURE IS WHEN 50% OF THE STRIPS SHOW SIGNS OF CRACKING. 2) MELTING SAID POLYMER BLEND; 3) RAMMING THE MOLTEN POLYMER BLEND INTO A MOULD SAID MOULD HAVING A CAVITY WHICH PRODUCES A THIN-WALLED ARTICLE HAVING A THIN SECTION LESS THAN 1MM IN THICKNESS AND WHEREIN THE THIN SECTION IS SUBSTANTIALLY CONTINUOUS FOR GREATER THAN 50MM IN THE DIRECTION OF FLOW OF THE MOLTEN POLYMER BLEND IN THE MOULD; AND 4) REMOVING FROM THE MOULD THE THIN-WALLED ARTICLE FORMED FROM THE POLYMER BLEND.
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