QUIMICA Y EL LIDER: diciembre 2009

jueves, 10 de diciembre de 2009

EFFECT OF HUMIDITY WHEN APLLYING FLOOR FINISH

The effects of humidity on the drying and performance of a floor finish is very important. High humidity retards the evaporation of water from the polish film, leaving the film soft, incompletely dry, and very Scuffable. Floor finish films, like latex paints, dry (harden) from the surface inward towards the flooring. Thus a floor finish which appears to be dry and feels dry to touch can in fact be wet and soft down close to the floor.

Adequate ventilation during and after applying a floor finish is very important. If the air in the area being finished is high in humidity, close the windows and run the air conditioner to lower the humidity. In the winter, turn up the heat to dry the air and also warm-up the substrate (flooring).

Problems caused by high humidity are:
1. Excessive scuffing and black marking from traffic until finish dries hard.
2. Poor detergent and water resistance due to the delay in finish cross-linking.
3. The threat and reality of “gluing” furniture to the floor.
4. Streaking and mop drag created by the coat being applied “biting” into preceding coats. (this phenomenon is caused by the applied coat re-emulsifying the previous coating that has not yet cure.)

Another important aspect in the drying of floor finish is the correlation between drying time and solids of the finish. Higher solids results in a thicker film developing on the floor and thus, a greater period of dry time being required between coats (sometimes in excess of one hour).

jueves, 3 de diciembre de 2009

LAS BONDADES DEL MAGNESIO PARA LA SALUD

MAS INFORMACION DE CLORURO DE MAGNESIO

Cloruro y magnesio (Cl y Mg): Éstos son otros dos importantes elementos de la sangre. El cloruro es particularmente importante para regular el equilibrio de líquidos en el organismo. El magnesio se encarga de las contracciones musculares y de sintetizar las proteínas.

El magnesio tiene múltiples acciones beneficiosas sobre el organismo. Se le puede considerar toda una defensa ya que contribuye a depurar la sangre, disolver los depósitos de colesterol de los vasos sanguíneos, activar y movilizar los leucocitos, y a favorecer la producción de anticuerpos,..

El magnesio es un metal divalente del grupo alcalino-térreo, que ocupa el sexto lugar en abundancia natural entre los elementos de la corteza terrestre. Aparece en combinación química con otros elementos, en particular, en los minerales carnalita, dolomita y magnesita, en muchos silicatos constituyentes de rocas y como sales, por ejemplo el cloruro de magnesio, que se encuentra en el mar y en los lagos salinos.

Es, además, un componente esencial del tejido animal y vegetal ya que está presente en todas las células; lo que explica su presencia en nuestra alimentación. El magnesio capta la energía solar y la potencia, formando compuestos químicos que los organismos son después capaces de sintetizar. Al mismo tiempo, permite liberar el oxígeno necesario para las funciones respiratorias.

Anti-estrés
La mitad del magnesio de nuestro organismo se encuentra en los huesos, y la otra mitad está implicada en procesos celulares, realmente importantes. Toma parte en el mantenimiento de la glucosa y otras partículas nutrientes, para que posteriormente se pueda aprovechar la energía de éstas.

Entre las principales funciones y propiedades del magnesio hay que destacar la activación de vitaminas, enzimas, la formación de estructuras óseas y dentales, proteínas y anticuerpos, el mantenimiento de la viscosidad del líquido sinovial y la ayuda en el metabolismo de síntesis de los lípidos. Además, tiene una misión anti-estrés, antitrombótica, antiinflamatoria y cardioprotectora.

Sin magnesio...

La falta de este mineral hace que los reflejos nerviosos y musculares se deterioren. Su carencia conlleva, además, vértigos, convulsiones y debilidad en los huesos, puesto que su presencia en ellos es muy importante. La escasez de magnesio está relacionada también con el aumento de la tasa de potasio.

Corregir las carencias

Cuando hay una carencia de magnesio en el organismo, ésta se puede corregir administrando diariamente magnesio

Es bueno para prevenir las enfermedades infantiles como la rubéola, sarampión, faringitis, viruela, tos ferina, alergia y en general todas las enfermedades que cursan con fiebre o inflamación.

Es muy bueno para prevenir las migrañas.

Es excelente para evitar la pérdida de audición que se produce por la exposición a ruidos más fuertes que los normales.

Es bueno para las embarazadas porque ayuda para disminuir la presión arterial. También es bueno para el dolor menstrual y otros síntomas que acompañan a la menstruación.

Sirve de broncodilatador pues relaja los músculos que rodean los bronquios y dicen que ha sido utilizado con éxito en ataque agudos de asma bronquial.

Reduce el riesgo de cálculos renales porque aumenta la solubilidad del calcio en la orina.

miércoles, 2 de diciembre de 2009

THE GREAT VERSATILITY OF POLYURETHANE EMULSIONS

Innovation formulas from Bayer.
The aqueous 1K polyurethane dispersion solution for all indoor wood and glass coatings
Bayhydrol® UH 2593/1 is a unique binder that adds value to your formulations for parquet, furniture, joinery and glass coatings. Durability, drying speed andappearance are the attributes that describe the product best.The ecological, green label is not only because it is a solvent free aliphatic polyurethane dispersion, but it is also based on renewable resources - fatty acids. The latter undergo self crosslinking properties eventually leading to its high performance.
In Parquet Coatings:
Bayhydrol® UH 2593/1 provides very high black heel mar resistance (BHMR) and surface hardness. The transparency, wood warmth and gloss make the product particularly interesting for formulating glossy coatings. The easiness of downglossing and the fast drying lead to excellent semigloss and matt finishes.
Crosslinking with Bayhydur® 305 increases coating resistance while keeping the excellent transparency and wood warmth. Bayhydrol® AH XP 2741 is the first choice for PAC blending due to the high compatibility.
Get Technical Assistanceon coatings formulations containing polyurethane dispersions.
In Furniture Coatings:
Bayhydrol® UH 2593/1 brings high blocking resistance and scratch resistance to the coating. Therefore it's an interesting partner for blending with acrylic dispersions in 1K-WB coatings. Stain blocking is excellent, so it's an ideal choice for formulating 1K clear primers. The fast drying and high transparency are the advantages of Bayhydrol® UH 2593/1 as blending partner in the 2K-WB coatings (see graphs below). Very promising results are achieved also in waterbased UV-curing coatings, where the addition of Bayhydrol® UH 2593/1 to the polyurethane dispersion for UV curing improves the water releaseof the coatings and reduces the white pores effect significantly.

GREEN CHEMICALS

The Green Seal certification is granted by the organization with that name and has a great number of members contributing with the requirements to pass a raw material or a chemical product as "green". Generally for a material to be green, has to comply with a series of characteristics like: near neutral pH, low volatility, non combustible, non toxic to aquatic life, be biodegradable as measured by oxygen demand in accordance with the OECD definition.
Also the materials have to meet with toxicity and health requirements regarding inhalation, dermal and eye contact. There is also a specific list of materials that are prohibited or restricted from formulations, like ozone-depleting compounds and alkylphenol ethoxylates amongst others. Please go to http://www.greenseal.com/ for complete information on their requirements.
For information on current issues regarding green chemicals, see the blog from the Journalist Doris De Guzman, in the ICIS at: http://www.icis.com/blogs/green-chemicals/.
Certification is an important — and confusing — aspect of green cleaning. Third-party certification is available for products that meet standards set by Green Seal, EcoLogo, Energy Star, the Carpet & Rug Institute and others.
Manufacturers can also hire independent labs to determine whether a product is environmentally preferable and then place the manufacturer’s own eco-logo on the product; this is called self-certification. Finally, some manufacturers label a product with words like “sustainable,” “green,” or “earth friendly” without any third-party verification.
“The fact that there is not a single authoritative standard to go by adds to the confusion,” says Steven L. Mack M.Ed., director of buildings and grounds service for Ohio University, Athens, Ohio.
In www.happi.com of June 2008 edition, there is a report of Natural formulating markets that also emphasises the fact that registration of "green formulas" is very confused at present, due to lack of direction and unification of criteria and that some governmental instittion (in my opinion the EPA) should take part in this very important issue.

QUALITY CERTIFICATIONS

What Is ISO 14001 And Should I Care?
Increased awareness of sustainable development gives environmentally credible companies a competitive edge in national and international markets. A certified Environmental Management System proves that your business is taking active steps to fulfill your responsibility.
What Occupational Health and Safety Assessment Series (OHSAS 18001) and Should I Care?
An OHSMS promotes a safe and healthy working environment by providing a framework that allows your organization to consistently identify and control its health and safety risks, reduce the potential for accidents, aid legislative compliance and improve overall performance.
OHSAS 18001 is the internationally recognized assessment specification for occupational health and safety management systems. It was developed by a selection of leading trade bodies, international standards and certification bodies to address a gap where no third-party certifiable international standard exists.
What Is ISO 9000 And Should I Care?
ISO 9000 consists of a series of Quality Management System standards that are designed to facilitate and enable consistency of a product or service and thereby ensure that customer requirements are met or exceeded. They can be applied in any manufacturing industry or service sector.
The value of certification to customers is evident, but the quality of the certificate is also important. All certificates are not equal.

VISGAGE POCKET VISCOSITY COMPARATOR

This is another simple viscosimeter , to check relative viscosity of oils (from light motor oils to heavy machinery and gear oils)and can be used on site without the use of stopwatch or thermometer. It consists of a plate and a spreading device, see details at : http://www.visgage.com/
The latest version for high viscosity liquids is the Efflux test Cup, that can be used for hot fluids, up to 50000 cps. The cup has internal pins to measure laminar flow instead of transitional flow out of the cup's botom and has different hole sizes to handle various viscosity ranges. See www.viscosity.com for more details.

HOW TO SELECT THE BEST SOLVENT FOR A CLEANING JOB

To clean heavy grease, resins, tar or heavy hydrocarbon residues, a solvent based cleaner is necessary for a fast and effective job. To select the appropriate solvent or solvent combination, there is a fundamental list of characteristics to check:
1-Flash Point: the highest the flash point, the lower the risk of ignition. Also if the flash point is above 140 F, the product can be shipped as non hazardous.
2-Toxicity: important to know if the solvent will be used outside or in enclosed areas and check the allowed exposure levels from the MSDS.
3-Odor: again, will it be used in enclosed areas, will you need an extraction hood, is the odor irritating?
4-Evaporation rate: if the evaporation rate is too slow it may leave residue or too slow drying, if too fast may have not enough time for cleaning.
5-Solvency or cleaning power:checking the Kauri Butanol
is an indication, the higher value the better.
6-What is the cost?: this might be a limitating factor in using the selected solvent in your product.
7-VOC: the volatile organic compound classification from a regulatory standpoint, may limit the use of the solvent.
8-Compatibility: with other components of the formulation. 9-Biodegradability: in water and land.

NOTAS DE UTILIDAD....COMO AGREGAR FRAGANCIA AL CLORO

HAY CIERTAS FRAGANCIAS QUE SON COMPATIBLES CON EL HIPOCHLORITO DE SODIO. LA MAYORIA DESACTIVAN EL CLORO O LO LIBERAN DE SOLUCION. SIN EMBARGO EL USO DE POCAS CANTIDADES DE FRAGANCIA PUEDE SER EMUSIONADA SIN SACRIFICAR MUCHO LA ESTABILIDAD. EN ESPECIAL POCA CANTIDAD DE FRAGANCIA DE LIMON O DE PINO LE DAN UNA BUENA CONNOTACION Y DEBEN SER AGRAGADAS, LUEGO DE AGREGAR UNA CANTIDAD SIMILAR DE LAURIL SULFATO DE SODIO CON OXIDOS DE AMINAS COMO EMULSIONANTES. NO MEZCLE LOS SURFACTANTES CON LA FRAGANCIA PREVIO A INCORPORARSE.

HLB: HYDROPHILIC / LIPOPHILIC BALANCE

This balance will determine a surfactant's relative solubility in water or oil.
The range of values for the HBL will determine its application and performance:
VALUE APPLICATION
3.5-6 Water in oil emulsifier
7-9 Wetting agent
8-18 Oil in Water emulsifier
13-15 Detergent
15-18 Solubilizer and microemulsions

The HLB value in the surfactants is given by the extent of etoxilation which results from the reaction of linear or aromatic alcohols with molecules of ethylene oxide.
Thus as a guide, 1-3 moles of etoxilation will give a value for the HLB round 3.5-6; 4-6 moles EO will result in a 7-9 HLB; 7-12 moles EO, 10-15 HLB; over 12 moles EO will give an HLB between 15-18.