I Have a Research Support System

Xu Qiu has a degree course Nanomaterials on Wednesday morning, and an elective course on Friday morning.

In addition, there is a Production Internship course in this semester, but this course is not taken every week, and the teaching content is usually arranged by the school system in the middle of the semester.

Usually it is to visit factories, workshops, production lines, etc. The teaching content of the three majors is different, and it lasts almost half a day to one day.

Compared with undergraduate students, postgraduate courses will be much less. Undergraduate students need to take about 150 credits, while masters only need to take more than 30 credits, and doctors only need to take less than 20 credits.

Chen Wanqing basically completed the courses in her first year of doctorate, so there are no courses this semester.

Therefore, she went to the Zhangjiang campus on Wednesday morning, while Xu Qiu left after lunch.

...

Room A501.

When Xu Qiu entered the door and saw Chen Wanqing resting on the sofa, he joked:

Teacher Wei can't control it here, is senior sister just being lazy?

I'm not lazy, I did a lot of work this morning, Chen Wanqing pointed her fingers and said:

The reaction of this submission seems to be good, so I added a capping agent. Trimethyltinthiophene has been reacted, and now I am capping bromothiophene, and I will also help you with your reaction. alright;

Also, I also took out the glassware soaked in the alkali tank yesterday, and cleaned it with an ultrasonic cleaner;

In addition, the products of the last Soxhlet extraction, that is, the first batch of materials, I took them out and dried them together in a vacuum oven.

Sister, you've worked hard. Xu Qiu said.

Diligence can make up for one's weakness, but when it comes to laziness, Duan Yun is a master at paddling, Chen Wanqing said:

He was in Zhangjiang before. For almost a week, he didn't do experiments, and he didn't know what he was doing with the computer every day.

I was wondering what his group would do, but he said at the group meeting that 'he did a synthesis experiment, but it was unsuccessful, presumably it was caused by too high a concentration, and then he lowered the concentration and tried again, but it still failed. This was unsuccessful, so subsequent experiments aimed to further reduce the concentration. '

If I hadn't been in Zhangjiang during that time, I would have been fooled by him.

Duan Yun looks honest, and he would do such a thing. This is the Yun experiment. Xu Qiu laughed.

It's not considered a cloud experiment. This result is actually his last week's data, but he didn't report it at last week's group meeting, but served as the report content of this group meeting. Chen Wanqing said.

Duan Yun is very witty, we can also learn from this method. Xu Qiu said.

It's fine if you don't get found out, but it's miserable if you get found out. Chen Wanqing said.

Then senior sister, you can rest for a while, I will go to the laboratory to have a look.

Okay, stay safe.

...

Putting on the protective equipment, Xu Qiu entered the A502 laboratory and walked to his fume hood.

There are two oil baths inside.

One is equipped with a reaction vessel, and it is still heating at 120 degrees Celsius, and the end-capping reaction of bromothiophene is in progress.

This time the nitrogen balloon is very firm, standing upright, and has the size of a solid ball.

It seems that after applying the vacuum silicone grease, the airtightness of the system is sufficient to maintain for more than 24 hours.

The reaction bottle is a two-necked flask, one of which is connected to a spherical condenser, and the other is plugged with a rubber stopper.

The syringe can be used to inject medicine from the rubber stopper. For example, the two capping agents used for capping are both liquid, so they can be injected directly.

If it is a solid reagent, such as a catalyst, it needs to be dissolved in a solvent before injection.

Of course, before injecting, make sure there is no air in the syringe.

Just like giving an injection in a hospital, spray some liquid first to exhaust the air.

After careful observation, Xu Qiu found that there was a circle of solid matter inside the reaction container bottle.

It should be that when the molecular weight of the polymer is relatively large, the solubility in the solution decreases, resulting in its precipitation.

Based on a comprehensive judgment, at least from the point of view of the air tightness of the system and the molecular weight of the product, the synthesis reaction of the second batch of PBT4T materials is relatively successful.

Xu Qiu looked at another oil bath.

This machine was used for Soxhlet extraction before, and the first batch of PBT4T materials wrapped in filter paper in the extraction tube had been taken away by Chen Wanqing and vacuum-dried, but the whole set of equipment had not been dismantled.

It should be that the senior sister was too busy and didn't take care of it, or of course she forgot.

The color of the solution in the Erlenmeyer flask below is very dark, which again shows that the molecular weight of the first batch of materials is low.

Xu Qiu poured the solvent in the Erlenmeyer flask into the waste liquid bucket, and then dismantled the device.

By the way, after helping the senior sister's equipment, he cleaned all the glass instruments in an ultrasonic cleaner.

This time the glass equipment does not need to be soaked in an alkali tank first, because it is relatively clean, and this equipment will be used after the second batch of materials has been reacted.

...

When Chen Wanqing came to the laboratory, she found that Xu Qiu had already done the finishing work for her, so she said:

The time for the capping reaction is almost ready, let's do the post-processing of the second batch of materials.

Xu Qiu turned off the heating device of the oil bath, then lifted the reaction vessel above the oil level of the oil bath, and waited for it to cool down naturally.

Sister, are you still submitting new responses today? Xu Qiu asked.

Forget it, it's too tiring to do experiments continuously, Chen Wanqing said:

Also, the performance of these two batches has not been tested yet. Let's make a few batches of devices with them first, otherwise the group will have nothing to report next week.

OK.

Xu Qiu used a disposable PE cup to collect methanol and prepare filter paper.

After waiting for the reaction vessel to drop to room temperature, remove the device, draw the solution with a disposable dropper, and drop it into methanol.

Different from the post-processing of the first batch of products, this time the solution dripped down, forming small blue round cakes, which slowly fell into the bottom of the cup.

And when the dropper goes down, about two milliliters of the solution is added to methanol, and the methanol solution is still transparent, close to colorless.

This shows that most of the products are separated out in solid form, and the molecular weight of the products is very high.

After the solution in the reaction bottle was blotted dry, there was still a ring of solid product on the inner wall of the bottle, forming a strip-shaped film.

Because this thing is already solid, there is no need to treat it with methanol.

Xu Qiu took it out with a stainless steel spatula and threw it into the methanol solution.

Then filter and let stand.

After finishing, Chen Wanqing said a little excitedly:

This time the molecular weight is very high, it should be the most successful one since I did the synthesis reaction.

Immediately, she changed her tone and said, However, according to the literature, the higher the molecular weight, the better.

That's right, although the higher the molecular weight, the better the photoelectric properties in theory, but the solubility will decrease accordingly, Xu Qiu said:

If the solubility is low to a certain extent, there is no way to form a film, and then no matter how good the performance is, it will not help.

I hope the performance of this batch of samples will be better.

Thank you Lan Shiyu for the 1000 starting point reward.