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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMaximum" xml:lang="en-US">Performance Stock Unit Fair Values Of RiskFree Interest Rate Maximum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMaximum" xml:lang="en-US">Performance stock unit fair values of risk-free interest rate maximum</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" xlink:label="loc_wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" xml:lang="en-US">Performance Stock Unit Fair Values Of RiskFree Interest Rate Minimum</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" xlink:to="lab_wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" xml:lang="en-US">Performance stock unit fair values of risk-free interest rate minimum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" xlink:label="loc_wlk_PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" xml:lang="en-US">Performance Stock Unit Fair Values Of Volatility Of Common Stock</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" xlink:to="lab_wlk_PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" xml:lang="en-US">Performance stock unit fair values of volatility of common stock.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMaximum" xlink:label="loc_wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMaximum" xml:lang="en-US">Restricted Stock Unit Fair Values Of Common Stock As Of The Measurement Maximum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMaximum" xml:lang="en-US">Restricted stock unit fair values of common stock as of the measurement maximum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMinimum" xlink:label="loc_wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMinimum" xml:lang="en-US">Restricted Stock Unit Fair Values Of Common Stock As Of The Measurement Minimum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMinimum" xml:lang="en-US">Restricted stock unit fair values of common stock as of the measurement minimum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesMeasurementDateMaximum" xlink:label="loc_wlk_StockOptionFairValuesMeasurementDateMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesMeasurementDateMaximum" xml:lang="en-US">Stock Option Fair Values Measurement Date Maximum</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_StockOptionFairValuesMeasurementDateMaximum" xlink:to="lab_wlk_StockOptionFairValuesMeasurementDateMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesMeasurementDateMaximum" xml:lang="en-US">Stock option fair values measurement date maximum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesMeasurementDateMinimum" xlink:label="loc_wlk_StockOptionFairValuesMeasurementDateMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesMeasurementDateMinimum" xml:lang="en-US">Stock Option Fair Values Measurement Date Minimum</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_StockOptionFairValuesMeasurementDateMinimum" xlink:to="lab_wlk_StockOptionFairValuesMeasurementDateMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesMeasurementDateMinimum" xml:lang="en-US">Stock option fair values measurement date minimum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesOfExpectedDividendYieldMaximum" xlink:label="loc_wlk_StockOptionFairValuesOfExpectedDividendYieldMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedDividendYieldMaximum" xml:lang="en-US">Stock Option Fair Values Of Expected Dividend Yield Maximum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedDividendYieldMaximum" xml:lang="en-US">Stock option fair values of expected dividend yield maximum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesOfExpectedDividendYieldMinimum" xlink:label="loc_wlk_StockOptionFairValuesOfExpectedDividendYieldMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedDividendYieldMinimum" xml:lang="en-US">Stock Option Fair Values Of Expected Dividend Yield Minimum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedDividendYieldMinimum" xml:lang="en-US">Stock option fair values of expected dividend yield minimum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesOfExpectedLifeMaximum" xlink:label="loc_wlk_StockOptionFairValuesOfExpectedLifeMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedLifeMaximum" xml:lang="en-US">Stock Option Fair Values Of Expected Life Maximum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedLifeMaximum" xml:lang="en-US">Stock option fair values of expected life Maximum</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesOfExpectedLifeMinimum" xlink:label="loc_wlk_StockOptionFairValuesOfExpectedLifeMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedLifeMinimum" xml:lang="en-US">Stock Option Fair Values Of Expected Life Minimum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedLifeMinimum" xml:lang="en-US">Stock option fair values of expected life minimum</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMaximum" xlink:label="loc_wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMaximum" xml:lang="en-US">Stock Option Fair Values Of Expected Volatility Of The Price Maximum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMaximum" xml:lang="en-US">Stock option fair values of expected volatility of the price maximum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMinimum" xlink:label="loc_wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMinimum" xml:lang="en-US">Stock Option Fair Values Of Expected Volatility Of The Price Minimum</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMinimum" xml:lang="en-US">Stock option fair values of expected volatility of the price minimum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesRiskFreeInterestRateMaximum" xlink:label="loc_wlk_StockOptionFairValuesRiskFreeInterestRateMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesRiskFreeInterestRateMaximum" xml:lang="en-US">Stock Option Fair Values Risk Free Interest Rate Maximum</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_StockOptionFairValuesRiskFreeInterestRateMaximum" xlink:to="lab_wlk_StockOptionFairValuesRiskFreeInterestRateMaximum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesRiskFreeInterestRateMaximum" xml:lang="en-US">Stock option fair values risk free interest rate maximum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockOptionFairValuesRiskFreeInterestRateMinimum" xlink:label="loc_wlk_StockOptionFairValuesRiskFreeInterestRateMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockOptionFairValuesRiskFreeInterestRateMinimum" xml:lang="en-US">Stock Option Fair Values Risk Free Interest Rate Minimum</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_StockOptionFairValuesRiskFreeInterestRateMinimum" xlink:to="lab_wlk_StockOptionFairValuesRiskFreeInterestRateMinimum" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_wlk_StockOptionFairValuesRiskFreeInterestRateMinimum" xml:lang="en-US">Stock option fair values risk free interest rate minimum.</link:label>
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_OptionAwardsMember" xlink:label="loc_wlk_OptionAwardsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_OptionAwardsMember" xml:lang="en-US">Option Awards [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_OptionAwardsMember" xlink:to="lab_wlk_OptionAwardsMember" />
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_StockAwardsMember" xlink:label="loc_wlk_StockAwardsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_StockAwardsMember" xml:lang="en-US">Stock Awards [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_StockAwardsMember" xlink:to="lab_wlk_StockAwardsMember" />
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_AlbertChaoMember" xlink:label="loc_wlk_AlbertChaoMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_AlbertChaoMember" xml:lang="en-US">Albert Chao [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_AlbertChaoMember" xlink:to="lab_wlk_AlbertChaoMember" />
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_JeanMarcGilsonMember" xlink:label="loc_wlk_JeanMarcGilsonMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_JeanMarcGilsonMember" xml:lang="en-US">Jean-Marc Gilson [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_JeanMarcGilsonMember" xlink:to="lab_wlk_JeanMarcGilsonMember" />
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_MStevenBenderMember" xlink:label="loc_wlk_MStevenBenderMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_MStevenBenderMember" xml:lang="en-US">M. Steven Bender [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_MStevenBenderMember" xlink:to="lab_wlk_MStevenBenderMember" />
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_RobertFBuesingerMember" xlink:label="loc_wlk_RobertFBuesingerMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_RobertFBuesingerMember" xml:lang="en-US">Robert F. Buesinger [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_RobertFBuesingerMember" xlink:to="lab_wlk_RobertFBuesingerMember" />
          <link:loc xlink:type="locator" xlink:href="wlk-20251231.xsd#wlk_JamesChaoMember" xlink:label="loc_wlk_JamesChaoMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_wlk_JamesChaoMember" xml:lang="en-US">James Chao [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wlk_JamesChaoMember" xlink:to="lab_wlk_JamesChaoMember" />
        </link:labelLink>
      </link:linkbase>
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
  <import namespace="http://xbrl.sec.gov/dei-sub/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-sub-2025.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <import namespace="http://fasb.org/srt/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd" />
  <import namespace="http://fasb.org/srt-types/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-types-2025.xsd" />
  <import namespace="http://xbrl.sec.gov/ecd-sub/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-sub-2025.xsd" />
  <import namespace="http://xbrl.sec.gov/ecd/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd" />
  <import namespace="http://www.xbrl.org/2006/ref" schemaLocation="http://www.xbrl.org/2006/ref-2006-02-27.xsd" />
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://fasb.org/srt-roles/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-roles-2025.xsd" />
  <element name="PayVsPerformanceDisclosureAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_PayVsPerformanceDisclosureAbstract" substitutionGroup="xbrli:item" />
  <element name="OptionAwardsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_OptionAwardsMember" substitutionGroup="xbrli:item" />
  <element name="StockAwardsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_StockAwardsMember" substitutionGroup="xbrli:item" />
  <element name="AlbertChaoMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_AlbertChaoMember" substitutionGroup="xbrli:item" />
  <element name="JeanMarcGilsonMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_JeanMarcGilsonMember" substitutionGroup="xbrli:item" />
  <element name="PerformanceStockUnitFairValuesOfClosingPrice" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_PerformanceStockUnitFairValuesOfClosingPrice" substitutionGroup="xbrli:item" />
  <element name="PerformanceStockUnitFairValuesOfRiskfreeInterestRateMaximum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMaximum" substitutionGroup="xbrli:item" />
  <element name="PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_PerformanceStockUnitFairValuesOfRiskfreeInterestRateMinimum" substitutionGroup="xbrli:item" />
  <element name="PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_PerformanceStockUnitFairValuesOfVolatilityOfCommonStock" substitutionGroup="xbrli:item" />
  <element name="RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMaximum" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMaximum" substitutionGroup="xbrli:item" />
  <element name="RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMinimum" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_RestrictedStockUnitFairValuesOfCommonStockAsOfTheMeasurementMinimum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesMeasurementDateMaximum" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesMeasurementDateMaximum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesMeasurementDateMinimum" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesMeasurementDateMinimum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesOfExpectedDividendYieldMaximum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesOfExpectedDividendYieldMaximum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesOfExpectedDividendYieldMinimum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesOfExpectedDividendYieldMinimum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesOfExpectedLifeMaximum" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesOfExpectedLifeMaximum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesOfExpectedLifeMinimum" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesOfExpectedLifeMinimum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesOfExpectedVolatilityOfThePriceMaximum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMaximum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesOfExpectedVolatilityOfThePriceMinimum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesOfExpectedVolatilityOfThePriceMinimum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesRiskFreeInterestRateMaximum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesRiskFreeInterestRateMaximum" substitutionGroup="xbrli:item" />
  <element name="StockOptionFairValuesRiskFreeInterestRateMinimum" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="wlk_StockOptionFairValuesRiskFreeInterestRateMinimum" substitutionGroup="xbrli:item" />
  <element name="InsiderTradingPoliciesandProceduresAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_InsiderTradingPoliciesandProceduresAbstract" substitutionGroup="xbrli:item" />
  <element name="AwardTimingDisclosureAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_AwardTimingDisclosureAbstract" substitutionGroup="xbrli:item" />
  <element name="MStevenBenderMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_MStevenBenderMember" substitutionGroup="xbrli:item" />
  <element name="RobertFBuesingerMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_RobertFBuesingerMember" substitutionGroup="xbrli:item" />
  <element name="JamesChaoMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="wlk_JamesChaoMember" substitutionGroup="xbrli:item" />
</schema>
