The search results provide information about different makeup primers, including their positive and negative aspects, ingredients, and materials. Here is a summary of the information:

1. e.l.f. Power Grip Primer: This gel-based and hydrating face primer is infused with powerhouse ingredients like Hyaluronic Acid, which moisturizes, preps, and smoothes the skin to perfection, improving the look and feel of the skin.

2. Freeman Beauty Restorative Glow Booster Serum + Makeup Primer: This lightweight hydrating serum and primer helps to soften, brighten, and smooth skin for longer-lasting makeup. It can be used as a serum or a primer.

3. NYX PROFESSIONAL MAKEUP Marshmellow Smoothing Primer: This vegan face primer has 10-in-1 skin benefits, including smoothing, softening, hydrating, soothing, evening tone, minimizing texture, blurring lines, adding a soft focus finish, and keeping makeup in place. It has a 100 percent vegan formula and no silicones.

4. Milk Makeup Hydro Grip Gripping Primer: This clean, silicone-free dewy makeup primer with hyaluronic acid grips makeup for up to 12 hours and hydrates skin to prevent meltdown and caking. It is highly rated by customers.

5. GXVE Beauty All Time Prime Prep & Smooth Oil: This hydrating, lightweight, non-comedogenic, multi-use skin-prepping and priming oil creates a smooth, dewy complexion. It is available at Sephora.

In summary, makeup primers are used to moisturize, prep, and smooth the skin, improving the look and feel of the skin. They can have different ingredients and materials, such as Hyaluronic Acid, vegan formulas, and non-comedogenic oils. Some primers can also have negative aspects, such as fragrances that may bother some people. It is important to evaluate the ingredients of makeup primers to ensure they are safe and effective for your skin type.