The phrase "acceptable materials" is correct and usable in written English.
You can use it when referring to items or substances that meet certain standards or criteria for a specific purpose.
Example: "The project guidelines specify that only acceptable materials should be used in the construction process."
Alternatives: "permissible materials" or "approved materials".
(A list of acceptable materials is here).
Titanium and its alloys are recognized as acceptable materials for many applications.
Unidentified religious experts helped the bureau shape the lists of acceptable materials, which independent scholars said omitted many important religious texts.
But the list grew to the tens of thousands, and the bureau decided instead to compile lists of acceptable materials in a plan called the Standardized Chapel Library Project.
The nature of the problem is both complex and varies from having to consider a large number of available materials and vague information in the early design stages, to a small number of acceptable materials and detailed information in the later design stages.
The nature of the problem is both complex and varying from having to consider a large number of available materials and vague information in the early design stages to a small number of acceptable materials and detailed information in the later design stages.
Virtually all works also will be fixed in acceptable material objects -- i.e., copies or phonorecords.
As for his other claims, Army doctors concluded he was "not acceptable material from a psychiatric viewpoint".
This trend is perhaps a rejection of high culture, an attempt to elevate fringe elements of pop culture to the status of socially acceptable material obsession.
In a more general sense, any attempt to prescribe what is and is not acceptable material in a novel must always be inherently censorious and ugly.
And as a copyright holder and creator, I don't want a single Walmart-like channel that controls access to my audience and dictates what is and is not acceptable material for me to create".
