A chemistry degree alone is insufficient. L-1B requires special knowledge of the company's products or an advanced level of knowledge of its processes and procedures, but the knowledge does not have to be unique or limited to only a few employees.
Argue the formulation set, not the diploma
Hypothetical example: the first draft of the petition devotes two pages to the chemist's degree and one paragraph to the company. Invert it. The degree shows she is a professional; the case is that she knows the company's proprietary micronutrient formulations, the blending order that prevents precipitation between components, the stability tests the company designed and the tolerances it enforces, and that this knowledge took five years and cannot be found outside the company.
Each claim needs a document: the formulation register, the procedure she authored, batch records, and a signed statement from the technical director. Then show that the U.S. work requires it: commissioning the new line against the Canadian standard and training staff.
The relationship between the companies must be a qualifying one, both must be doing business, and her year abroad must be continuous and within three years of filing. A U.S. officer will accept that chemists are common and still approve if the company's knowledge is shown to be specific and scarce.