tell me the reason plastic can not re-usable on chemistry. why can not re assemble them?

ChatGPT

Plastics are typically challenging to reassemble or reuse through chemical processes for several reasons:

1. Polymer Complexity: Plastics are composed of long chains of polymers, which are large molecules made up of repeating units. These polymers can be very complex and vary significantly depending on the type of plastic (e.g., polyethylene, polypropylene, PVC). Breaking down these complex polymers and reassembling them is a complex and energy-intensive process.
2. Irreversible Cross-Linking: Some plastics, such as thermosetting plastics like epoxy and phenolic resins, contain cross-linking chemical bonds that form a three-dimensional network. These cross-links are irreversible, making it difficult to break them down and reassemble the material into its original form.
3. Contaminants: Used plastics often contain contaminants like dirt, oils, and other materials that can interfere with chemical processes. These impurities can make it challenging to obtain high-purity plastic materials through chemical recycling.
4. Degradation: Plastics can undergo degradation when exposed to heat, light, and oxygen over time. This degradation can result in changes to the chemical structure of the plastic, making it difficult to return it to its original properties.
5. Energy Intensive: Recycling plastics chemically can be energy-intensive and expensive. The high temperatures and pressures required to break down the polymers and reassemble them into new materials can make the process economically impractical in many cases.
6. Limited Reusability: Even when chemical recycling is possible, it often results in the production of lower-quality plastics with properties inferior to virgin materials. This limits the number of times plastics can be recycled chemically before they become unsuitable for most applications.

While chemical recycling techniques are continually improving, they still face significant challenges in terms of efficiency, cost-effectiveness, and scalability. Mechanical recycling, such as melting and reshaping plastics, remains a more common and economically viable method for reusing plastics. Innovations in recycling technologies are ongoing, and researchers are exploring ways to make plastics more recyclable and environmentally friendly.

is plastic extracted from oil?

ChatGPT

Yes, plastic is typically derived from petroleum, which is a fossil fuel. The process of making plastic from petroleum involves several chemical steps, and it is called petrochemical production. Here’s a simplified overview of how plastic is produced from oil:

1. Crude Oil Extraction: Crude oil is extracted from underground reservoirs through drilling and pumping. Crude oil is a mixture of hydrocarbons and other compounds.
2. Refining: Crude oil is transported to refineries, where it undergoes a refining process to separate various components, including gasoline, diesel fuel, jet fuel, and petrochemical feedstocks.
3. Petrochemical Production: The petrochemical feedstocks obtained from the refining process are then used as raw materials for the production of plastics. The primary petrochemicals used in plastic production are ethylene, propylene, and other monomers.
4. Polymerization: In polymerization, these monomers are chemically bonded together in a controlled process to form long chains of polymers, which are the building blocks of plastics.
5. Additives and Processing: Various additives, such as stabilizers, plasticizers, and colorants, are mixed with the polymer to give the plastic its desired properties. The resulting mixture is then processed into various forms, such as pellets, sheets, or molded products.
6. Manufacturing: The processed plastic is used to manufacture a wide range of products, from packaging materials and automotive parts to toys and consumer goods.

It’s important to note that not all plastics are made from petroleum. Some plastics can be produced from alternative feedstocks, such as natural gas or renewable resources like biomass. These alternative feedstocks can help reduce the environmental impact of plastic production and lessen dependence on fossil fuels. However, petroleum-based plastics are still the most common and widely used types of plastics.

what kind of studies or researches are process about plastic reuse or reassemble nowadays? and were they got result? tell me anything about it.

ChatGPT

Research and studies related to plastic reuse and reassembly are ongoing in various fields, including materials science, chemistry, and engineering. These efforts aim to develop more sustainable methods for recycling and reusing plastics, reduce environmental impacts, and minimize plastic waste. Here are some areas of research and recent developments in the field of plastic reuse and reassembly:

1. Chemical Recycling: Scientists are working on improving chemical recycling techniques, such as depolymerization and pyrolysis, which break down plastics into their constituent monomers or smaller chemical compounds. These processes can potentially yield higher-quality recycled plastics and reduce the need for virgin plastic production. Research has made progress in optimizing these processes and scaling them up for industrial use.
2. Biodegradable Plastics: Researchers are developing biodegradable plastics made from renewable resources like plant starch, cornstarch, or algae. These plastics can break down naturally in the environment, reducing the persistence of plastic waste. However, challenges remain in terms of their cost-effectiveness, performance, and widespread adoption.
3. Mechanical Recycling: Innovations in mechanical recycling technologies are aimed at improving the efficiency of sorting, cleaning, and reprocessing used plastics. Advanced sorting and separation techniques, along with better recycling equipment, are being explored to increase the quality and yield of recycled materials.
4. Plastic Upcycling: Some researchers are exploring methods to “upcycle” plastics into higher-value products, such as textiles, building materials, and chemical feedstocks. For example, recycled PET bottles can be used to make polyester fabrics, reducing the need for virgin polyester production.
5. Biotechnological Solutions: Biotechnology is being applied to develop microorganisms that can break down and digest plastics, potentially offering a more environmentally friendly approach to plastic degradation. Enzymes that can degrade specific types of plastics have also been studied.
6. Eco-Friendly Additives: Scientists are researching and developing additives that can enhance the recyclability and biodegradability of plastics. These additives can help mitigate the environmental impact of plastic waste.
7. Circular Economy Initiatives: Governments, businesses, and organizations are promoting the concept of a circular economy for plastics. This involves designing products and packaging for reuse and recycling, as well as implementing extended producer responsibility (EPR) programs to incentivize responsible plastic management.
8. Policy and Regulation: Policymakers and regulators are implementing laws and regulations aimed at reducing single-use plastics, increasing recycling rates, and promoting sustainable plastic use. These policies are designed to drive industry innovation and consumer behavior change.

It’s important to note that while significant progress has been made in plastic reuse and recycling, challenges remain, including economic viability, scalability, and consumer behavior. The development and adoption of more sustainable practices and technologies are ongoing efforts, and the effectiveness of these solutions will continue to evolve over time.

안드로이드 앱에 내가 만든 THREE.JS 뷰어를 로드 해야할 일이 생겼다.

threejs 캔버스가 들어간 HTML파일을 준비하고 다음과 같이 로드 해주면 된다. 단, 안드로이드 웹 앱에서 자바스크립트를 실행하려면 다음과 같은 설정이 필요하다.

webView.addJavascriptInterface(this, "android");
webView.loadUrl("javascript:android.onData(functionThatReturnsSomething)");

---

참고

https://blog.naver.com/urbanbaseinc/221672052557

https://stackoverflow.com/questions/3298597/how-to-get-return-value-from-javascript-in-webview-of-android

웹 페이지 상에 보여지는 부분만 캡쳐하는 것이 아닌 포함하는 웹페이지 전체영역을 한번에 캡쳐하는 방법이 있다.

이 방법은 크롬, 엣지에서만 사용 할수 있다.

• 브라우저 정보
  Chrome(115.0.5790.111)
  Edge (115.0.1901.188)

방법은 다음과 같다.

1. 캡쳐할 웹페이지에 접속한다.
2. F12 키를 눌러 개발자 도구창을 열어준다.
   • 크롬 : 설정 > 도구 더보기 > 개발자 도구
   • 엣지 : 설정 > 기타 도구 > 개발자 도구 ( Ctrl + Shift + I )
3. Ctrl + Shift + P 를 열어 명령어 창을 연다.
4. 명령어 입력 박스에 “스크린샷” 이라고 입력한다. 영문 브라우저 일 경우 “Screenshot”
5. “원본 크기 스크린샷 캡쳐” 메뉴를 클릭한다. 영문 브라우저 일 경우 “Full Size Screenshot”
6. 페이지 캡쳐 이미지가 내 컴퓨터로 다운로드 된다.

// 클립보드로 내용 복사
// window.navigator.clipboard.writeText( [string] )

window.navigator.clipboard.writeText( 'content what you want' ).then( () => {
   console.log( 'copy done' );
} );

// HTML 요소 내용 복사
// HTML document 내용 생략
<body>
   <textarea id="myTextArea"/>
</body>
<script>
   const myTextArea = document.getElementById( 'myTextArea' );
   window.navigator.clipboard.writeText( myTextArea.value ).then( () => {
      alert('copy done');
   });
</script>
...

https://curryyou.tistory.com/480

https://developer.mozilla.org/en-US/docs/Web/API/Navigator/clipboard