Clive Palmer's company Queensland Nickel donated almost $290,000 to his troubled political party just two weeks before sacking 237 workers from its Townsville refinery.

The company announced the redundancies on Friday after the Queensland government refused Mr Palmer's December request that it act as a guarantor for a $35 million loan.

But a new Electoral Commission of Queensland document shows the company donated $288,516 to the Palmer United Party on December 31.

The "Special Reporting Event Return" document is signed by managing director Clive Mensink, who is Mr Palmer's nephew.