Strategically adding weak points along microscopic chains called polymers (高分子聚合物) actually makes them harder to tear, researchers report in the June 23 Science. Polymers are used in car tires, and therefore the findings could help reduce plastic pollution as tires wear down over time.

When tires rub against the road, they drop microplastics of rubber and plastic polymers, which pollute waterways and air. Every year, tires release an estimated 6 million metric tons of these microplastics into environment. Stronger polymers that break apart less easily could limit the amount of particles shed annually.

To make such tough materials, Stephen Craig, a chemist at Duke University, and colleagues added molecules called cross-linkers to the polymers. These cross-linkers connected these polymer chains to their many neighbors, and they were specifically designed to break apart easily. At the microscopic scale, the polymers act like a tangle (乱团) of spaghetti with the cross-linkers holding them all together and helping them keep their shape, says Craig’s collaborator Shu Wang, a chemist at MIT. When the team stretched the polymer spaghetti, the individual cross-linkers broke easily, as expected. But the larger tangle material required more force to break than they expected.

The secret to the increased toughness lies in the path the tear has to take, Craig says. The tear goes through the easy-to-break cross-linkers rather than through the tougher polymer chains. Each broken connection follows the path of least resistance but avoiding the long polymer chains means breaking many cross-linkers, which requires more stretching force overall.

This isn’t the first time researchers have used weak connectors to make polymers stronger. But unlike in similar materials, the increased toughness doesn’t come at the expense of other beneficial properties like stiffness (风度). Craig says he hopes the findings will help extend the lifetimes of car tires and plastics, potentially limiting annual microplastic pollution.

My father died when I was nine, and I remember doing the household chores to help my mother. I hated changing the vacuum cleaner (真空吸尘器) bag and picking up things the machine did not suck up.

Twenty years later, in 1978, I was doing chores at home alongside my wife. One day the vacuum cleaner was screaming away, and I had to empty the bag because I could not find a replacement for it. With this lifelong hatred of the way the machine worked, I decided to make a bagless vacuum cleaner.

Easier said than done, of course. I didn’t realize that I would spend the next five years perfecting my design, a process that resulted in 5,127 different prototypes (设计原型). By the time I made my 15th prototype, my third child was born. By 2,627, my wife and I were really counting our pennies. By 3,727, my wife was giving art lessons for some extra cash, and we were getting further and further into debt. These were tough times, but each failure brought me closer to solving the problem.

I just had a passion for the vacuum cleaner as a product, but I never thought of going into a business with it. In the early 1980s, I started trying to get licensing agreements for my technology. The reality was very different, however. The major vacuum makers had built a business model based on the profits from bags and filters (滤网). No one would license my idea, not because it was a bad one, but because it was bad for business.

That gave me the courage to keep going, but soon after, the companies that I had talked with started making machines like mine. I had to fight legal battles on both sides of the Atlantic to protect the patents on my vacuum cleaner. However, I was still in financial difficulties until 1993, when my bank manager personally persuaded Lloyds Bank to lend me $1 million. Then I was able to go into production. Within two years, the Dyson vacuum cleaner became a best-seller in Britain.

Today, I still embrace risk and the potential for failure as part of the process. Nothing beats the excitement of invention. Go out and brainstorm your ideas. You are not bound to any rules - in fact, the stranger and riskier your idea, the better.

The trend is clear: more and more people are walking around with wireless headphones. Some of the best selling headphones are from Apple, which have a high price. This price is beyond many budgets and many of us are simply not willing to pay that amount.

We Have Found the Solution

We’re recently discovered a brand that is overtaking the famous one in many countries. It is iHeadphones. The iHeadphones have an attractive design that is very similar to the most recognized brand. They even top the competition in many aspects. The most important thing is that they are compatible (兼容的) with Android and IOS. They are currently only available to buy online.

Main Characteristics

Different colors: you can choose the one that goes best with your style.

Long battery life: more than 8 hours of your favorite music thanks to its powerful battery.

Better price: iHeadphones cost less than half of what you'd pay for AirPods, with characteristics that are similar or superior to the competition.

How Can You Buy It?

You can place your order online through the official website www.iHeadphones.com. It will be sent to your home.

Only during the launch period, the company is offering a large promotion for this product through the website. And if that is not enough, they will also offer a discount for mass purchases.

Limited Sale

50% off only during the launch period on the website. Buy it now! Limited sale.