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  <xs:element id="shc_IotronIndustriesCanadaIncIotronMember" abstract="true" name="IotronIndustriesCanadaIncIotronMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="shc_ForeignCurrencyGainLossAndGainLossOnEmbeddedDerivative" abstract="false" name="ForeignCurrencyGainLossAndGainLossOnEmbeddedDerivative" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="shc_WriteOffOfDeferredDebtIssuanceCostAndDebtDiscount" abstract="false" name="WriteOffOfDeferredDebtIssuanceCostAndDebtDiscount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="shc_SeniorNotesDue2027Member" abstract="true" name="SeniorNotesDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="shc_LitigationSettlementAmountAwardedFromOtherPartyBeforePreJudgmentInterest" abstract="false" name="LitigationSettlementAmountAwardedFromOtherPartyBeforePreJudgmentInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="shc_InterestRateCapJune2020Member" abstract="true" name="InterestRateCapJune2020Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="shc_CashProceedsToSponsorsRatioToInvestedCapital" abstract="false" name="CashProceedsToSponsorsRatioToInvestedCapital" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="shc_EthyleneOxideTortLitigationGeorgiaMember" abstract="true" name="EthyleneOxideTortLitigationGeorgiaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
</xs:schema>
