EVA film quality requirements and incoming inspection

1.Appearance inspection:EVA surface has no stains,flatnass,translucent and clear embossing.

2.Measure with a precision 0.01mm thickness gauge, measure at least 5 points in the amplitude direction, take the average value, the thickness conforms to the agreed thickness, and the allowable tolerance is ±0.03mm

Measured with a steel ruler with an accuracy of 1mm, the amplitude is in line with the agreed size, and the allowable tolerance is ±2-3.0mm

3.Light transmittance inspection

1)Take the eva film size of 50mmX50mm, use 50mmX50mmX1mm glass, and laminate the glass/eva film/glass

2)Put the above sample in the laminator, heat to 100C, vacuum for 5mins, then press 0.5Mpa, hold for 5mins; then put it in the curing box, cross-link and solidify according to the curing temperature and time required by the product, then take it out and cool To room temperature.

3)Inspect according to GB2410

4.Cross-linking degree inspection

1)Apparatus and appliances

The capacity is 500ml to 1000ml, 24" ground round bottom flask; reflux condenser with 24" ground mouth; electric heating mantle or electric heating oil bath with temperature controller; vacuum oven; use 0.125mm stainless steel wire mesh, cut out 80mmX40mm, fold in half into a 40mm square, fold into 6mm on both sides and fix it. The bag is open at the top of the process.

2)Reagents

Xylene A.R grade

3)Sample preparation

Take a piece of the adhesive film and superimpose the TPT/adhesive film/adhesive film/glass, then cure and crosslink according to the usual one-time curing process, (or according to the manufacturer's process requirements), cut the crosslinked film into small pieces stand-by.

4)Inspection steps
Wash, dry, and weigh the stainless steel wire mesh bag to W1 (accurate to 0.01g)

Take the sample 1g±0.01g, put it into a stainless steel wire mesh bag, and weigh it as W2 (accurate to 0.01g)

Seal the mouth of the bag to make a sample bag and weigh it as W3 (accurate to 0.01g)

The sample package is suspended in a flask under the reflux condenser with a thin iron wire, and 1/2 xylene solvent is added to the flask, heated to about 140C, the solvent is boiled and refluxed for 4-6 hours, and the reflux rate is maintained at 20 drops/min-40 drops /Minute

Take out the sample package by cooling, hang to remove the solvent drop, then put it in a vacuum oven, control the temperature at 140C, the vacuum degree is 0.08Mpa, dry for 3 hours, completely remove the solvent

Take the sample pack out of the vacuum oven and place it in a desiccator to cool for 20 minutes, then take it out and weigh it as W4 (accurate to 0.01g). The result is calculated as:

C=[1-(W3-W4)/(W2-W1)]X100

In the formula:

C----crosslinking degree

W1----Empty bag weight (g)

W2----The weight of the bag with the sample (g)

W3----Sample package weight (g)

W4----The weight of the sample package after solvent extraction and drying (g)

Peel strength test

1)Take two pieces of film with a size of 300mmX20mm as samples, and laminate them according to TPT/film/film/peeling respectively
2)Curing according to the usual one-time curing process
3)Inspect according to GB/T2790

UV aging resistance test

Place the film in the aging box and irradiate continuously for 100h, visually compare

Uniformity test

Take 10 pieces of film of the same size for weighing, and then compare the weight of each film, the maximum and minimum should not exceed 1.5%