Dec 7 (Reuters) - Shares in Belgian plastics company Recticel jumped on Tuesday after investors backed the sale of its engineered foams business, a deal some analysts said might deter a hostile bid from Austrian rival Greiner that they had criticised as too low.

Shareholders on Monday gave the green light for Recticel to sell the foams unit to U.S.-based Carpenter Co., which had made a binding 656 million euro ($739 million) offer in October.

Recticel, which is on track to become a "pure-play" insulation company, expects regulatory approval in the coming months.

Its shares were up 6.17% at 17.20 euros at 1151 GMT.

Greiner, keen to buy the foams business, had planned to buy a 27% stake in Recticel from its top shareholder Compagnie du Bois Sauvage for 13.50 euros each and extend the offer to other investors.

However, some analysts had criticised the offer as too low, and European Union regulators opened an investigation into the potential deal in November, saying it could hurt competition and lead to price hikes.

ING researchers said they believed Greiner's deal was now significantly less probable, while Berenberg analyst Christoph Greulich said the low bid price meant it had been "highly unlikely to succeed anyway."

KBC Securities said that, despite the setback, Greiner could still hold on to its plan to buy Bois Sauvage's stake and become and important shareholder.

Greiner did not immediately respond to a request for comment.

Recticel CEO Olivier Chapelle told reporters he did not expect any great difficulties with antitrust regulators over the deal with Carpenter Co.

"If this were the case," he added, "I believe remedies could be found."

He did not rule out considering other possible takeover bids more favourable to shareholders.

Recticel is planning to sell its Bedding business line to Aquinos Group, and expects Compagnie du Bois Sauvage to support the deal.

($1 = 0.8879 euros) (Reporting by Sarah Morland and Diana Mandiá Editing by Mark Potter)