September 13, 2018
On Thursday, September 13, 2018, the President signed into law:
H.R. 4318, the "Miscellaneous Tariff Bill Act of 2018," which provides for duty suspensions and reductions for specified chemicals and other items through December 31, 2020.
Donald J. Trump (1st Term), President Donald J. Trump Signs H.R. 4318 into Law Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/336227