UPDATE 1-Polymer firm Synthomer expects profit hit in tough market

(Adds details on outlook, peers, background)

Oct 25 (Reuters) - Polymer maker Synthomer Plc predicted on Friday it would fall short of market expectations for underlying pretax profit this year as a slowing global economy hammers chemical producers globally, sending its shares 13% lower.

The company, which added that it expects a slower business environment to continue into next year, said underlying pretax profit would be about 10% below both last year as well as its current estimate of the consensus of market expectations, which it put at 135.3 million pounds ($173.82 million).

The warning came a day after industry heavyweights BASF and Dow Inc posted sharp falls in profit due to a sharp drop in demand for chemicals used in plastics.

"Depressed European industrial activity combined with increased political and economic uncertainties have resulted in an overall slower trading environment throughout Q3," Synthomer said.

The London-based company also said its paper segment was weak and that it expected both unit margins and volumes of SBR, a key ingredient in paper production, to be about 10% behind last year.

The estimates excluded the impact of Synthomer's purchase of Ohio-headquartered Omnova Solutions Inc, which it agreed in July for an enterprise value of $824 million in a bid to help it bolster its footprint in Europe and Asia and penetrate into China. ($1 = 0.7784 pounds) (Reporting by Tanishaa Nadkar in Bengaluru; editing by Patrick Graham)