Kumho Petrochemical Co, the petrochemical unit of South Korea\'s Kumho Asiana Group, said Thursday that its net profit nearly tripled in the second quarter from a year earlier on robust synthetic rubber sales. Net profit came to 189.5 billion won (US$179.2 million) in the April-June period, compared with 63 billion won a year ago, Kumho Petrochemical said in a regulatory filing. Sales rose 40 percent on-year to 1.7 trillion won in the period, and operating profit shot up 92.7 percent to 275 billion won. \"A sharp rise in synthetic rubber sales contributed to the strong second-quarter performance,\" said Kumho Petrochemical. Sales in synthetic rubber soared 24.7 percent to 9.82 billion won, accounting for 57.5 percent of total sales. Shares of Kumho Petrochemical rose 1.23 percent to 246,500 won on the Seoul bourse on Thursday.