Polymers
Bayani Gaba-gaba
Polymers are the materials that quietly shape modern life: the casing of your phone, the bottle your water comes in, the insulation around every cable in your home. The word itself tells the story - a polymer is built from many (poly) repeating units (mers) joined into long molecular chains. How those chains are arranged, and whether they can be re-melted or are locked permanently, decides everything about how a polymer behaves and how a designer can work with it.
This note covers the 0445 Materials-option polymer objectives in depth: how polymers are classified, the stock forms they are bought in, their key properties and environmental impact, the named thermoplastics from nylon and HDPE through to PLA, the two thermosetting resins you must know, and the growing family of biopolymers. Concrete product examples run throughout so you can justify a material choice, not just name one.
Manufura
- demonstrate knowledge of polymers, including biopolymers, and understand their classification, stock forms, properties, environmental impact and uses
- demonstrate knowledge of thermo polymers, for example: - nylon - low- and high-density polyethylene (LDPE and HDPE) - polyethylene terephthalate (PET) - polyvinyl chloride (PVC) - acrylic (PMMA) - polystyrene (PS) - polypropylene (PP) - acrylonitrile-butadiene-styrene (ABS) - polylactic acid (PLA)
- demonstrate working knowledge of the following thermosetting polymers: - polyester resin - epoxy resin.
Takardar Darasi
Akwai a cikin manhajar Green Bridge
Zazzage manhajar Green Bridge CBT a wayar ka ko kwamfyuta ka don samun cikakkiyar bayanan darasi, tambayoyin aiki, da ƙari.
Nazarin Darasi
Barka da kammala darasi akan Polymers. Yanzu da kuka bincika mahimman raayoyi da raayoyi, lokaci yayi da zaku gwada ilimin ku. Wannan sashe yana ba da ayyuka iri-iri Tambayoyin da aka tsara don ƙarfafa fahimtar ku da kuma taimaka muku auna fahimtar ku game da kayan.
Za ka gamu da haɗe-haɗen nau'ikan tambayoyi, ciki har da tambayoyin zaɓi da yawa, tambayoyin gajeren amsa, da tambayoyin rubutu. Kowace tambaya an ƙirƙira ta da kyau don auna fannoni daban-daban na iliminka da ƙwarewar tunani mai zurfi.
Yi wannan ɓangaren na kimantawa a matsayin wata dama don ƙarfafa fahimtarka kan batun kuma don gano duk wani yanki da kake buƙatar ƙarin karatu. Kada ka yanke ƙauna da duk wani ƙalubale da ka fuskanta; maimakon haka, ka kallesu a matsayin damar haɓaka da ingantawa.
- Which statement about thermosetting polymers is correct? A. They soften every time they are heated B. They can be re-melted and recycled repeatedly C. They cure permanently and cannot be reshaped by heating D. They are always made from renewable plant sources Answer: C
- Which polymer is best suited to a transparent, weather-resistant sign that must be polished to a clear finish? A. Acrylic (PMMA) B. Low-density polyethylene (LDPE) C. Nylon D. Polypropylene (PP) Answer: A
- LDPE is softer and more flexible than HDPE mainly because: A. LDPE is a thermoset and HDPE is a thermoplastic B. LDPE chains are branched and pack less tightly than HDPE chains C. LDPE contains a plasticiser and HDPE does not D. HDPE is made from plants and LDPE from oil Answer: B
- Which property makes nylon a good choice for small gears and bearings? A. It is optically transparent B. It is biodegradable C. It is tough, hard-wearing and self-lubricating with low friction D. It melts at a very low temperature Answer: C
- Which statement about PLA is correct? A. It is an oil-based thermoset B. It is bio-based and biodegradable but composts best in industrial conditions C. It cannot be used in 3D printing D. It is the toughest polymer in the syllabus Answer: B
Akwai a cikin manhajar Green Bridge
Zazzage manhajar Green Bridge CBT a wayar ka ko kwamfyuta ka don samun cikakkiyar bayanan darasi, tambayoyin aiki, da ƙari.
Akwai a cikin manhajar Green Bridge
Zazzage manhajar Green Bridge CBT a wayar ka ko kwamfyuta ka don samun cikakkiyar bayanan darasi, tambayoyin aiki, da ƙari.
Littattafan da ake ba da shawarar karantawa
Yi Aikin Tambayoyin Gwaji
Kana son yin aikin tambayoyin gwaji kan Polymers? Sauke manhajar Green Bridge CBT don samun tambayoyin gwaji da cikakkun jarrabawa akan wannan batu.
Sauke Manhajar Daga Google Playstore
Duk abin da kake buƙata don yin fice a JAMB, WAEC & NECO.
