Polypore International (NYSE:PPO): Polypore (NYSE:PPO) is declining sharply after one its customers, Korea’s LG Chem, indicated that it would enter the battery separator business. Polypore already has a battery separator business, and the company spent $100M in July 2011 to expand its lithium-ion battery separator capacity for electric vehicles. In a note to investors, DA Davidson said that LG Chem’s announcement could create a significant overhang on Polypor. The firm, however, did estimate that it would take a “significant” amount of time for LG Chem to develop a battery separator solution. Nevertheless the firm downgraded the stock to Neutral from Buy and slashed its target on the shares to $45 from $73. In mid-afternoon trading, Polypore dropped $15.38, or 28.30%, to $38.96. The shares closed at $38.08, down $16.26 or 29.92% on the day. They have traded in a 52-week range of $42.43 to $74.21.

Quicksilver Resources (NYSE:KWK): Quicksilver Resources announced that it intends to spend approximately $370M in 2012 for drilling and completion and related oil and gas activities. This projected spending includes approximately $302M for drilling and completion activities, $46M for gathering and $22M for leasehold. The shares closed at $5.01, down $0.27 or 5.11% on the day. They have traded in a 52-week range of $5.07 to $15.98.

Rex Energy Corp. (NASDAQ:REXX): Brean Murray not Baird downgraded Rex Energy due to dilution from its 7M share equity offering expected to price tonight. The shares closed at $9.46, down $1.15 or 10.84% on the day. They have traded in a 52-week range of $9.67 to $18.00.

Radioshack Corp. (NYSE:RSH): RadioShack downgraded to hold from buy at griffen securities price target lowered to $8 from $20. The shares closed at $7.18, down $3.05 or 29.81% on the day. They have traded in a 52-week range of $9.15 to $16.70.

Sprint Nextel Corp. (NYSE:S): Radioshack’s dismal report lead shareholders of Sprint to press the sale button due to concerns of weakness on their retail partnership. The shares closed at $2.12, down $0.04 or 1.85% on the day. They have traded in a 52-week range of $2.10 to $6.45.

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To contact the reporter on this story: Derek Hoffman at staff.writers@wallstcheatsheet.com

To contact the editor responsible for this story: Damien Hoffman at editors@wallstcheatsheet.com

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