<exportButton class="MagentoUiComponentExportButton">
    <argument name="data" xsi:type="array">
        <item name="config" xsi:type="array">
            <item name="options" xsi:type="array">
                <item name="cvs" xsi:type="array">
                    <item name="value" xsi:type="string">csv</item>
                    <item name="label" xsi:type="string" translate="true">CSV</item>
                    <item name="url" xsi:type="string">profilers/export/gridToCsv</item>
                </item>
            </item>
        </item>
    </argument>
</exportButton>

<?php
namespace ...ProfilersControllerAdminhtmlExport;

public function __construct(
MagentoFrameworkAppActionContext $context,
MagentoFrameworkAppResourceConnection $resource
) {
    $this->resource = $resource;
    return parent::__construct($context);
}
public function execute()
{

    $this->_view->loadLayout(false);
    $fileName = 'profilers.csv';
    $table = $this->resource->getTableName('profilers');
    $objectManager = MagentoFrameworkAppObjectManager::getInstance();
    $this->_fileFactory = $objectManager->create('MagentoFrameworkAppResponseHttpFileFactory');
    return $this->_fileFactory->create(
        $fileName,
        $table,
        DirectoryList::VAR_DIR
    );

}