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By Andrea Johnson and Christopher Reich

NEW YORK, Nov 5 (IFR) - Abbott's new pharmaceuticals business AbbVie Inc completed the biggest ever dollar-denominated debt issue in the US high-grade market on Monday, raising $14.7 billion in a six-part deal.

AbbVie, which will house Abbott's proprietary pharmaceuticals business as part of the company's plan to split into two, sold notes with maturities ranging from three years to 30 years.

The "old" Abbott will focus on the company's medical devices, diagnostics and nutritional product businesses.

The deal came on a record day for dollar volume, with issuers selling a staggering $22.1 billion of debt on the eve of one of the tightest presidential elections in memory.

"With a deal of this size they could not afford to wait until after the election to get it done," said an investment-grade corporate credit strategist who has covered the Abbott spinoff.

"Whichever way the election goes it will have an effect on spreads, and Abbott couldn't afford to take a punt on the market changing."

Barclays, Bank of America Merrill Lynch, JP Morgan, Morgan Stanley, BNP Paribas and Societe Generale were active bookrunners on the Baa1/A rated deal.

Demand from investors was exceptionally strong, with book size heard as high as $47 billion.

"We're not too surprised to read that demand is high," said Carol Levenson, credit strategist at Gimme Credit.

"This deal was expected and provides a relatively rare opportunity to purchase a triple 'B' big pharma name."

Proceeds of the sale will be used to make a cash distribution to Abbott, as provided by the terms of the separation agreement, pay related fees and expenses, and for general corporate purposes.

Abbott last week said it had commenced a cash tender offering for $7.7 billion in outstanding notes.

The previous record for a pure US dollar-denominated deal was held by two other pharmaceuticals companies, according to Thomson Reuters/IFR data: Roche , which sold a $13.5 billion five-part deal in February 2009, and Pfizer Inc , which issued a $13.5 billion four-part deal in March 2009.

The Roche deal included a $3 billion one-year floater, which is too short a maturity to be counted toward the total.

GE Capital is in second position with an $11 billion three-part deal from March 2002, followed by WorldCom's $10.1 billion three-part deal from May 2001.

The AbbVie deal also eclipses the $9.8 billion four-part deal brought by United Technologies in May 2012, which until Monday had been the biggest deal of the year.

AbbVie sold $3.5 billion of three-year fixed-rated notes at Treasuries plus 85 basis points (bp), tighter than its launch price guidance of Treasuries plus 90 basis points area.

It sold $500 million of three-year floating-rate notes at Libor plus 76bp, in line with guidance.

The company also sold $4 billion of five-year notes at Treasuries plus 110bp, $1 billion of six-year notes at Treasuries plus 140bp, $3.1 billion of 10-year notes at Treasuries plus 130bp and $2.6 billion of 30-year notes at Treasuries plus 160bp.

(Reporting By Christopher Reich and Andrea Johnson; Editing by Ciara Linnane and Marc Carnegie)