Preston — The fall semester at the University of New Haven ended two weeks ago, and adjunct chemistry professor Thomas Sharp turned in his grades.

At age 69, Sharp is on his third career stint, having returned to teaching college-level chemistry after working as a chemist at Pfizer Inc. in Groton for nearly 20 years.

Relaxing in the living room of his Bunny Road home in Preston a few days after he had turned in the final grades for the 30 students in his quantitative analysis lab, Sharp didn’t hesitate to answer why he has no interest in retiring.

“When the semester ends, two days after, I’m walking around saying, ‘Now what do I do?’” Sharp said. “I’m well established enough in my profession that I’m comfortable. I have no reason to retire.”

Actually, Sharp’s next semester at the UNH main campus in West Haven could be his busiest yet. He will lecture in his usual spring semester class, instrumental methods, and teach a lab in that subject. He also will have two undergraduate chemistry students working with him on research projects. One of them will tackle a problem of Sharp’s creation. The student will try to find out why the quantitative analysis lesson he has presented to students is yielding a 40 percent to 50 percent deviation from the expected results.

Sharp said he suspects the cause but looks forward to seeing what his research student discovers.

“Usually, an undergraduate student will research something you already know the answer,” Sharp said. “I suspect the answer. If it works, that student would be worthy of co-authorship of a paper. That’s the carrot.”

Sharp will be doing some research as well in the coming semester. He was hired by another UNH professor to help with a grant-funded research project.

The only downside to Sharp’s comfortable late-career work is the hour-plus commute to West Haven from rural Preston. He likes to make the drive one day a week for classes and labs but expects this coming busy semester will find him on campus two or three days a week.

He recalled one snowy November commute a few years ago, when he had to hug the edge of the breakdown lane to feel the rumble strips to be sure he still was on the road.

Sharp, who grew up in Illinois, attended and later taught at colleges from Utah to Indiana and Texas, where he was a faculty chemistry professor at Texas A&M University. In 1991, he was laid off at Texas A&M and learned of an opening for a chemist at Pfizer in Groton.

He and his family moved to Connecticut that year and, 25 years ago, moved into the house on Bunny Road with a view of picturesque Amos Lake. He and his wife separated in 2000, and their five adult children live in locations across the country. Daughter Kathy Sharp lives in Portland, Ore. Son Rob and three grandchildren are in Louisville, Ky. Chuck and Scot are in Colorado, and Erik is in Kansas.

In 2009, what he called the “Pfizer purge” reached Sharp after 18 years. It was not unexpected, he said, and not unwelcome, since he was “ready to bail” on the company by then. He was close to retirement age, received a good 13 weeks of severance pay plus an amount for each of his 18 years there.

But Sharp had no intention of retiring. He taught freshman chemistry for a year at the University of Connecticut Storrs campus in 2009-10.

“It was fun while it lasted,” he said. He was replaced by a post-doctorate student the following year.

He worked another year at UConn doing research for a pharmaceutical professor before landing at UNH in the fall 2011 semester.

Chemistry is Sharp’s profession, but he has other “creative outlets.”

He has two beehives at his Preston home, producing about 30 to 40 pounds of local wildflower honey under the label Amos Lake Apiary. He also has started making wine with grapes from a neighbor across Amos Lake.

A Midwest native, Sharp nurtured a passion for tall ships, and in 1990 in Texas he learned that the Texas Seaport Museum in Galveston was seeking to train volunteers to work the rigging on the tall ship the Elissa. He was hooked.

In Connecticut, he couldn’t crack the door at the Mystic Seaport, but in 2000 his daughter told him about a replica tall ship, Friendship of Salem in Salem, Mass., that was looking for volunteers. The ship, a three-masted square rigger, was built in 1997, a replica of an 18th century West Indies trading vessel based in Salem. The ship was captured by the British in the War of 1812.

Sharp had hoped to sail aboard Friendship to Baltimore to celebrate the 200th anniversary of the War of 1812, but an extensive inspection revealed significant wood rot. The ship was hauled to Maine for repairs, and there it remains. Sharp keeps in touch with the crew and volunteers, attending a Christmas party with the group recently, but he fears by the time the ship is seaworthy again, the crew and volunteers will have drifted away, aged or lost interest.

He also volunteered for four years aboard the 1960 HMS Bounty when it visited New London and then was homeported in Fall River, Mass. He was not on the ship when it sank in Hurricane Sandy off the coast of North Carolina in October 2012.

His other “creative outlet” is country dancing, mostly line dancing at the Brown Derby in Montville or at Dance Country in Gales Ferry. Each had pre-Christmas week parties.

Sharp hasn’t been to Galveston and the Texas Seaport Museum in 30 years, but looking past the busy spring semester at UNH, he plans to attend the American Society for Mass Spectrometry conference in Houston in June.

“So, I might go back to Galveston,” Sharp said.

c.bessette@theday.com