Parti sportive in resina composita in fibra di carbonio lunga PA12 resistente alle alte temperature automotive

PA12 Plastic

Polyamide (PA) is commonly known as nylon, and long carbon chain nylon refers to the variety of nylon with more than 10 methylene between adjacent amide bonds in the main chain of large molecules, such as PA11, PA12, PA1010, PA1212, PA1012, etc. The performance of PA12 is similar to that of PA11, but due to the shortage of castor oil, the raw material used to produce PA11, all countries are using PA12 instead of PA11.

PA12 is nylon 12, also known as polydodecactam, polylauractam, is a long carbon chain nylon. The basic material for its polymerization is butadiene, a semi-crystalline - crystalline thermoplastic material. Nylon 12 is the most widely used long carbon chain nylon, in addition to most of the general properties of nylon, low water absorption, and has high dimensional stability, high temperature resistance, corrosion resistance, good toughness, easy processing and other advantages. Compared with PA11, another long carbon chain nylon material, the price of butadiene, the raw material of PA12, is only one third of the price of castor oil, the raw material of PA11. It can replace PA11 and be applied in most scenes, and has a wide range of applications in automobile fuel pipe, air brake hose, submarine cable, 3D printing and many other fields.

characteristic

In long chain nylon, compared with other nylon materials, PA12 has great advantages, such as the lowest water absorption rate, the lowest density, low melting point, impact resistance, friction resistance, low temperature resistance, fuel resistance, good dimensional stability, good anti-noise effect. PA12 has the properties of PA6, PA66 and polyolefin (PE, PP) at the same time, achieving the combination of lightweight and physical and chemical properties, and has advantages in performance. The following table shows the performance data:

Advantage

There are a large number of non-polar methylene groups in nylon 12, which makes nylon 12 molecular chain more compliant. The amide group in nylon 12 is polar, and the cohesion energy is very large, it can form hydrogen bonds between the molecules, so that the molecular arrangement is regular. Therefore, nylon 12 has high crystallinity and high strength. Nylon 12 has low water absorption, good low temperature resistance, good air tightness, excellent alkali and oil resistance, medium resistance to alcohol, inorganic dilute acid and aromatic hydrocarbons, good mechanical and electrical properties, and is a self-flameout material.

1) Density

The relative density of nylon 12 is only 1.01-1.03, which is the smallest among all engineering plastics, which has a certain effect on reducing the quality of vehicles and reducing fuel consumption. When compared by unit volume, nylon 12 has advantages in price and performance.

2) Melting point

The melting point of nylon 12 is 172-178℃, slightly lower than nylon 11, can fully meet the requirements of automobile fuel pipe and brake pipe working environment temperature.

3) Water absorption

As we all know, the biggest disadvantage of nylon products is large water absorption, dimensional stability is difficult to ensure. And PA12 has the lowest water absorption rate of nylon products, this is due to the methylene molecules in nylon 12 greatly reduce the hydrophilic groups, which makes nylon 12 has a great advantage.

4) Impact strength

Impact strength is an important technical index, especially for nylon 12 pipe often exposed to air. Nylon 12 under -20℃ and -40℃ according to the standard test, no fracture phenomenon, fully meet the requirements of use. Nylon 12 has excellent impact resistance.

5) Low temperature performance

Nylon 12 has the lowest brittleness temperature of -70 degrees Celsius, so it can be widely used in low-temperature resistant parts.

6) Flexibility

The influence of plasticizer on the physical properties of nylon 12 is concentrated on the elastic modulus of resin. Nylon 12 has three basic types of resin, their main difference is due to the plasticizer content of different forms of flexibility. The elastic modulus of resin decreases with the increase of extractable component content of plasticizer.

7) Low wear and low friction performance

Nylon 12 has excellent low abrasion and low friction properties and self lubricating properties, so the friction noise of nylon 12 products is very low. The table below shows the values obtained for nylon 12 and other plastics by Tabor disk tests.

8) Fuel resistance

Nelle automobili, la miscela di carburante ossigenato, carburante ad alto contenuto aromatico e alcol attualmente utilizzata può causare la rottura di molti materiali dei tubi. Dopo il test, in questo ambiente possono essere utilizzati solo elastomeri di nylon 11, nylon 12 e resina fluorocarbonica. Quasi altri tipi di nylon si sciolgono sotto l'azione del carburante per automobili, determinando un cambiamento di dimensioni.

9) Resistenza alla soluzione di cloruro di zinco

Sotto la vettura si trova cloruro di zinco. A determinate temperature e umidità, il sale sulla strada reagisce con la lamiera di acciaio zincato o il primer contenente zinco per formare il cloruro di zinco corrosivo. Inoltre, l'invecchiamento dell'ozono, le radiazioni ultraviolette, le condizioni di temperatura e così via, porteranno diversi gradi di danno alle parti, riducendone la durata.
Il nylon 12 è molto resistente alla soluzione di cloruro di zinco. Poiché non vi è alcun doppio legame insaturo nel nylon 12 che è suscettibile all'attacco dell'ozono, non si verifica l'invecchiamento dell'ozono. Inoltre, anche la resistenza ai raggi UV del Nylon 12 è eccellente.

10) Eccellenti prestazioni elettriche

La lunga struttura a catena di carbonio del nylon conferisce eccellenti proprietà elettriche. A causa del basso assorbimento d'acqua del nylon a catena di carbonio lunga, ha ancora eccellenti proprietà dielettriche nell'ambiente umido, che non è posseduto dal nylon a catena di carbonio corta come il nylon 6 e il nylon 66.

Applicazione

PA12 è il nylon a catena lunga di carbonio più utilizzato. Oltre ad avere la maggior parte delle proprietà generali del nylon ordinario, ha un basso assorbimento d'acqua, un'elevata stabilità dimensionale, resistenza alle alte temperature, resistenza alla corrosione, buona tenacità, facilità di lavorazione e altri vantaggi. Rispetto al PA11, un altro materiale in nylon a catena lunga di carbonio, il prezzo del butadiene, la materia prima del PA12, è solo un terzo del prezzo dell'olio di ricino, la materia prima del PA11. Può sostituire PA11 ed essere applicato nella maggior parte delle scene e ha una vasta gamma di applicazioni nei tubi del carburante per automobili, nei tubi dei freni ad aria compressa, nei cavi sottomarini, nella stampa 3D e in molti altri campi.