Polyvinylether Refrigerator Oil for Mildly Flammable HFC Compatibility
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Refrigerating machine oils used with HFC refrigerants face challenges in compatibility, lubricity, and thermal/chemical stability, necessitating the development of specialized oils that enhance safety through flame retardancy.
Innovation Solution
A refrigerating machine oil comprising a polyvinylether with a specific molecular weight range and molecular weight ratio, used in conjunction with a mildly flammable hydrofluorocarbon refrigerant, such as difluoromethane, 1,3,3,3-tetrafluoropropene, or 2,3,3-tetrafluoropropene, to enhance safety and compatibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hydrocarbon oils are used with CFC/HCFC refrigerants, then good lubricity and compatibility are achieved, but flame safety deteriorates due to the flammability of hydrocarbon oils
Solution Approach 1:
The invention changes the chemical composition parameters by using polyvinylether instead of hydrocarbon oils, and selects HFC refrigerants with specific flame resistance properties, thereby achieving both good lubricity/compatibility and improved flame safety
Solution Approach 2:
The invention creates a composite refrigeration system by combining polyvinylether oil with HFC refrigerants, where the polyvinylether provides excellent lubricity and compatibility while the HFC refrigerant contributes flame resistance, achieving a balanced performance
2Ease of manufacture
If polyvinylether with Mn<500 or Mn>2000 is used, then manufacturing is easier, but flame retardancy and lubricity performance deteriorate
Solution Approach 1:
The invention optimizes the molecular weight parameters by specifying Mn between 500-2000 and Mw/Mn ratio between 1.10-1.25, which balances the ease of polymerization control with excellent flame retardancy and lubricity performance
3Device complexity
If polyvinylether with Mw/Mn<1.10 or Mw/Mn>1.25 is used, then polymerization process is simpler, but compatibility and thermal stability deteriorate
Solution Approach 1:
The invention optimizes the molecular weight distribution parameters by specifying Mw/Mn ratio between 1.10-1.25, which balances polymerization process simplicity with excellent compatibility and thermal stability performance
Data Source
AI summary
The present invention provides a refrigerating machine oil comprising a polyvinylether having a structural unit represented by the following formula (1):wherein R1, R2, and R3 may be the same or different from each other and each represent a hydrogen atom or a hydrocarbon group, R4 represents a divalent hydrocarbon group or an ethereal oxygen-containing divalent hydrocarbon group, R5 represents a hydrocarbon group, m represents an integer of 0 or more, and in the case where m is 2 or more, a plurality of R4 may be the same or different from each other, a number average molecular weight Mn is 500 or more and 2000 or less, a ratio of a weight average molecular weight Mw to a number average molecular weight Mn, Mw/Mn, is 1.10 or more and 1.25 or less, and the refrigerating machine oil is used with a mildly flammable hydrofluorocarbon refrigerant.